Ejemplo n.º 1
0
 public FzTupleEntity(FzTupleEntity old)
 {
     foreach (Object item in old._valuesOnPerRow)
     {
         this.ValuesOnPerRow.Add(item);
     }
 }
Ejemplo n.º 2
0
        /// <summary>
        ///  The variable i for getting the previous logicality
        /// </summary>
        //private Boolean SatisfyItem(List<String> itemCondition, FzTupleEntity tuple, int i)
        //{
        //    int indexAttr = Convert.ToInt32(itemCondition[0]);
        //    String dataType = this._attributes[indexAttr].DataType.DataType;
        //    Object value = tuple.ValuesOnPerRow[indexAttr];//we don't know the data type of value
        //    int count = 0;
        //    String fs = itemCondition[2];
        //        //fs = itemCondition[2].Substring(1, itemCondition[2].Length - 2);;
        //    ContinuousFuzzySetBLL conFS = null;
        //    DiscreteFuzzySetBLL disFS = null;
        //    if (itemCondition[1] == "->" || itemCondition[1] == "→")
        //    {
        //        //fs = fs.Substring(1, fs.Length - 2);
        //        conFS = new ContinuousFuzzySetBLL().GetByName(fs);
        //        disFS = new DiscreteFuzzySetBLL().GetByName(fs);//2 is value of user input
        //    }
        //    if (conFS != null)//continuous fuzzy set is priorer than discrete fuzzy set
        //    {
        //        //itemCondition[1] is operator, uValue is the membership of the value on current cell for the selected fuzzy set
        //        Double uValue = FuzzyCompare(Convert.ToDouble(value), conFS, itemCondition[1]);
        //        uValue = Math.Min(uValue, _uRelation);//Update the min value
        //        if (uValue != 0)
        //        {
        //            if (i != -1 && _memberships.Count > 0)// Getting previous logicality
        //                _memberships.Add(_itemConditions[i].nextLogic);
        //            _memberships.Add(uValue.ToString());
        //            count++;
        //        }
        //    }
        //    if (disFS != null && conFS == null)
        //    {
        //        Double uValue = FuzzyCompare(Convert.ToDouble(value), disFS, itemCondition[1]);
        //        uValue = Math.Min(uValue, _uRelation);//Update the min value
        //        if (uValue != 0)
        //        {
        //            if (i != -1 && _memberships.Count > 0)// Getting previous logicality
        //                _memberships.Add(_itemConditions[i].nextLogic);
        //            _memberships.Add(uValue.ToString());
        //            count++;
        //        }
        //    }
        //    if (disFS == null && conFS == null)
        //    {
        //        //if (fs.Contains("\""))
        //        //    fs = fs.Substring(1, fs.Length - 2);
        //        if (ObjectCompare(value, fs, itemCondition[1], dataType))
        //        {
        //            count++;
        //        }
        //    }
        //    if (count == 1)//it mean the tuple is satisfied with all the compare operative
        //    {
        //        return true;
        //    }
        //    return false;
        //}
        private Boolean SatisfyItem(List<String> itemCondition, FzTupleEntity tuple, int i)
        {
            int indexAttr = Convert.ToInt32(itemCondition[0]);
            String dataType = this._attributes[indexAttr].DataType.DataType;
            Object value = tuple.ValuesOnPerRow[indexAttr];//we don't know the data type of value
            int count = 0;
            String fs = itemCondition[2];
            //fs = itemCondition[2].Substring(1, itemCondition[2].Length - 2);;
            ConFS conFS = null;
            DisFS disFS = null;
            string path = Directory.GetCurrentDirectory() + @"\lib\";
            if (itemCondition[1] == "->" || itemCondition[1] == "→")
            {
                //fs = fs.Substring(1, fs.Length - 2);
                conFS = new FuzzyProcess().ReadEachConFS(path + fs + ".conFS");
                disFS = new FuzzyProcess().ReadEachDisFS(path + fs + ".disFS");//2 is value of user input
            }
            if (conFS != null)//continuous fuzzy set is priorer than discrete fuzzy set
            {
                //itemCondition[1] is operator, uValue is the membership of the value on current cell for the selected fuzzy set
                Double uValue = FuzzyCompare(Convert.ToDouble(value), conFS, itemCondition[1]);
                uValue = Math.Min(uValue, _uRelation);//Update the min value
                if (uValue != 0)
                {
                    if (i != -1 && _memberships.Count > 0)// Getting previous logicality
                        _memberships.Add(_itemConditions[i].nextLogic);
                    _memberships.Add(uValue.ToString());
                    count++;
                }
            }
            if (disFS != null && conFS == null)
            {
                Double uValue = FuzzyCompare(Convert.ToDouble(value), disFS, itemCondition[1]);
                uValue = Math.Min(uValue, _uRelation);//Update the min value
                if (uValue != 0)
                {
                    if (i != -1 && _memberships.Count > 0)// Getting previous logicality
                        _memberships.Add(_itemConditions[i].nextLogic);
                    _memberships.Add(uValue.ToString());
                    count++;
                }
            }
            if (disFS == null && conFS == null)
            {
                //if (fs.Contains("\""))
                //    fs = fs.Substring(1, fs.Length - 2);
                if (ObjectCompare(value, fs, itemCondition[1], dataType))
                {
                    count++;
                }
            }

            if (count == 1)//it mean the tuple is satisfied with all the compare operative
            {
                return true;
            }

            return false;
        }
Ejemplo n.º 3
0
        /// <summary>
        /// 
        /// </summary>
        public Boolean Satisfy(List<Item> list, FzTupleEntity tuple)
        {
            this._resultTuple = new FzTupleEntity() { ValuesOnPerRow = tuple.ValuesOnPerRow };//select * from rpatient where age <> "old"
            _uRelation = Convert.ToDouble(tuple.ValuesOnPerRow[tuple.ValuesOnPerRow.Count - 1]);
            this._memberships = new List<string>();

            String logicText = String.Empty;

            for (int i = 0; i < list.Count; i++)
            {
                if (list[i].elements.Count == 3)// single expression: age='young'.
                {
                    if (SatisfyItem(list[i].elements, tuple, i - 1))
                        logicText += "1" + list[i].nextLogic;
                    else
                        logicText += "0" + list[i].nextLogic;
                }
                else// Multiple expression: weight='heavy' not height>165
                {
                    List<Item> subItems = CreateSubItems(list[i].elements);
                    Boolean end = Satisfy(subItems, tuple);
                    if (end)
                        logicText += "1" + list[i].nextLogic;
                    else
                        logicText += "0" + list[i].nextLogic;
                }
            }

            logicText = ReplaceLogicality(logicText);
            _resultTuple.ValuesOnPerRow[_resultTuple.ValuesOnPerRow.Count - 1] = UpdateMembership(_memberships);
            return CalulateLogic(logicText);
        }
Ejemplo n.º 4
0
        public bool OpenFuzzyDatabase(FdbEntity fdb)
        {
            try
            {
                SqliteConnection connection = new SqliteConnection(fdb.ConnString);
                DataSet ds = new DataSet();

                ds.Tables.Add(connection.GetDataTable("SELECT * FROM SystemScheme", "system_scheme"));//Table [0]
                ds.Tables.Add(connection.GetDataTable("SELECT * FROM SystemRelation", "system_relation"));//Table [1]
                ds.Tables.Add(connection.GetDataTable("SELECT * FROM SystemAttribute", "system_attribute"));//Table [2]
                ds.Tables.Add(connection.GetDataTable("SELECT * FROM SystemQuery", "system_query"));//Table [3]

                ///Load Schemes////////////////////////////////////////////////////////////////////////////////////////
                foreach (DataRow row in ds.Tables["system_scheme"].Rows)
                {
                    String schemeName = row[1].ToString();
                    FzSchemeEntity tmpScheme = new FzSchemeEntity(schemeName);
                    DataTable tmpDt = new DataTable();
                    tmpDt = connection.GetDataTable("SELECT * FROM SystemAttribute Where SchemeID=" + Convert.ToInt16(row[0]));

                    if (tmpDt != null)
                    {
                        foreach (DataRow item in tmpDt.Rows)
                        {
                            Boolean primaryKey = Convert.ToBoolean(item[1]);
                            String attributeName = Convert.ToString(item[2]);
                            String typeName = Convert.ToString(item[3]);
                            String domain = Convert.ToString(item[4]);
                            String description = Convert.ToString(item[5]);

                            FzDataTypeEntity tmpDataType = new FzDataTypeEntity(typeName, domain);
                            FzAttributeEntity tmpAttribute = new FzAttributeEntity(primaryKey, attributeName, tmpDataType, description);

                            tmpScheme.Attributes.Add(tmpAttribute);
                        }

                        fdb.Schemes.Add(tmpScheme);
                    }
                }

                ///Load Relations//////////////////////////////////////////////////////////////////////////////////////////
                foreach (DataRow row in ds.Tables["system_relation"].Rows)
                {
                    String relationName = row[1].ToString();
                    int schemeID = Convert.ToInt16(row[2]);//To get scheme is referenced
                    String schemeName = connection.GetValueField("SELECT SchemeName FROM SystemScheme WHERE ID=" + schemeID).ToString();
                    DataTable tmpDt = new DataTable();
                    tmpDt = connection.GetDataTable("SELECT * FROM " + relationName);

                    FzRelationEntity tmpRelation = new FzRelationEntity(relationName);//Relation only content relation name, but scheme referenced and list tuples is null
                    tmpRelation.Scheme = FzSchemeDAL.GetSchemeByName(schemeName, fdb);//Assign scheme referenced to relation, but tuples is null

                    int nColumns = tmpRelation.Scheme.Attributes.Count;//Get number columns of per row

                    if (tmpDt != null)//
                    {
                        foreach (DataRow tupleRow in tmpDt.Rows)
                        {
                            List<Object> objs = new List<object>();

                            for (int i = 0; i < nColumns; i++)//Add values on per row from tupleRow[i]
                            {
                                //values += tupleRow[i].ToString();
                                objs.Add(tupleRow[i]);
                            }

                            FzTupleEntity tmpTuple = new FzTupleEntity() { ValuesOnPerRow = objs };
                            tmpRelation.Tuples.Add(tmpTuple);
                        }
                    }

                    fdb.Relations.Add(tmpRelation);
                }

                ///Load Queries////////////////////////////////////////////////////////////////////////////////////////////
                foreach (DataRow row in ds.Tables["system_query"].Rows)
                {
                    FzQueryEntity tmpQuery = new FzQueryEntity(row[1].ToString(), row[2].ToString());
                    fdb.Queries.Add(tmpQuery);
                }

                return true;
            }
            catch (SQLiteException ex)
            {
                throw new Exception("ERROR:\n" + ex.Message);
                //return false;
            }
        }
Ejemplo n.º 5
0
        private FzTupleEntity UpdateMembership(FzTupleEntity t1, FzTupleEntity t2)
        {
            Double u1 = Convert.ToDouble(t1.ValuesOnPerRow[t1.ValuesOnPerRow.Count - 1]);
            Double u2 = Convert.ToDouble(t2.ValuesOnPerRow[t2.ValuesOnPerRow.Count - 1]);
            t1.ValuesOnPerRow[t1.ValuesOnPerRow.Count - 1] = Math.Min(u1, u2);//Update the membership

            return t1;
        }
Ejemplo n.º 6
0
        private FzTupleEntity IsSatisfyExpression(String[] splitedList, FzTupleEntity tuple)
        {
            FzTupleEntity result = new FzTupleEntity() { ValuesOnPerRow = tuple.ValuesOnPerRow };

            int indexAttr = Convert.ToInt32(splitedList[0]);
            String dataType = this._attributes[indexAttr].DataType.DataType;
            Object value = tuple.ValuesOnPerRow[indexAttr];//we don't know the data type of value
            int count = 0;

            DiscreteFuzzySetBLL disFS = new DiscreteFuzzySetBLL().GetByName(splitedList[2]);//2 is value input
            ContinuousFuzzySetBLL conFS = new ContinuousFuzzySetBLL().GetByName(splitedList[2]);

            if (conFS != null)//continuous fuzzy set is priorer than discrete fuzzy set
            {
                Double uValue = FuzzyCompare(Convert.ToDouble(value), conFS, splitedList[1]);//1 is operator
                Double uRelation = Convert.ToDouble(tuple.ValuesOnPerRow[tuple.ValuesOnPerRow.Count - 1]);
                if (uValue != 0)
                {
                    result.ValuesOnPerRow[tuple.ValuesOnPerRow.Count - 1] = Math.Min(uValue, uRelation);
                    count++;
                }
            }

            if (disFS != null && conFS == null)
            {
                Double uValue = FuzzyCompare(Convert.ToDouble(value), disFS, splitedList[1]);
                Double uRelation = Convert.ToDouble(tuple.ValuesOnPerRow[tuple.ValuesOnPerRow.Count - 1]);
                if (uValue != 0)
                {
                    result.ValuesOnPerRow[tuple.ValuesOnPerRow.Count - 1] = Math.Min(uValue, uRelation);
                    count++;
                }
            }

            if (disFS == null && conFS == null)
            {
                if (ObjectCompare(value, splitedList[2], splitedList[1], dataType))
                {
                    count++;
                }
            }

            if (count == 1)//it mean the tuple is satisfied with all the compare operative
            {
                return result;
            }

            return null;
        }
Ejemplo n.º 7
0
        /// <summary>
        /// -Get expression (expression maybe content more than one operators): 20<age=young and height>150
        /// -Split expression to list string: first element is index of attribute, after that odd elements is operator and even element is value to compare(maybe fuzzy value)
        /// -Format condition pair of index attribute and value compare (operator is between) => 3> 20 and 3=young and 5>150
        /// -Split condition formated to list of string[] items: 1.index of attribute; 2.operator; 3.value compare(maybe fuzzy); 4.logicality
        /// -Loop to end list string[] splited: and check
        /// </summary>
        public FzTupleEntity IsSatisfy(FzTupleEntity tuple)
        {
            FzTupleEntity previous = null;// = new FzTupleEntity();
            Boolean flag = true;//flag for and logicality
            String and = "";

            String condition = FormatCondition(this._conditionText);
            List<String[]> itemsEx = GetItemExpression(condition);//condition must be formated, each itemsEx consists of 4 members

            for (int i = 0; i < itemsEx.Count; i++)
            {
                if (itemsEx[i][3] == " and ")
                {
                    FzTupleEntity current = IsSatisfyExpression(itemsEx[i], tuple);
                    if (current == null)
                    {
                        flag = false;
                        if (and == " and ")
                            previous = null;
                    }
                    else
                    {
                        if (and == " not ")
                        {
                            previous = null;
                        }
                        else if (previous != null)
                        {
                            previous = UpdateMembership(previous, current);
                        }
                        else
                        {
                            if (and == " and ")
                                previous = null;
                            else
                                previous = current;
                        }
                    }

                    and = " and ";
                }
                else if (itemsEx[i][3] == " or ")
                {
                    FzTupleEntity current = IsSatisfyExpression(itemsEx[i], tuple);
                    if (current != null)
                    {
                        if (and == " not ")
                        {
                            previous = null;
                        }
                        else if (previous != null)
                        {
                            previous = UpdateMembership(previous, current);
                        }
                        else
                            previous = current;
                    }
                    else
                    {
                        if (and == " and ")
                            previous = null;
                    }

                    flag = true;
                    and = " or ";
                }
                else if (itemsEx[i][3] == " not ")
                {
                    FzTupleEntity current = IsSatisfyExpression(itemsEx[i], tuple);
                    if (current != null)
                    {
                        if (and == " not " || and == " and ")//this not belong to this expression
                        {
                            previous = null;
                        }
                        else if (previous != null)
                        {
                            previous = UpdateMembership(previous, current);
                        }
                        else//previous == null
                            previous = current;
                    }
                    else
                    {
                        if (previous == null)
                            previous = null;
                    }

                    flag = true;
                    and = " not ";

                }
                else//With no zlogicality, end of the while
                {
                    FzTupleEntity current = IsSatisfyExpression(itemsEx[i], tuple);
                    if (current != null)
                    {
                        if (and == " not ")
                        {
                            previous = null;
                        }
                        else if (and == " and ")
                        {
                            if (previous != null)
                                previous = UpdateMembership(previous, current);
                            else
                                previous = null;
                        }
                        else if (previous != null)
                        {
                            previous = UpdateMembership(previous, current);
                        }
                        else//mean previous =null
                        {
                            if (flag)
                            {
                                previous = current;
                            }
                            else//error heres
                                previous = null;
                        }
                    }
                    else
                    {
                        if (and == " and ")
                            previous = null;
                    }
                }
            }

            return previous;
        }
Ejemplo n.º 8
0
 //IMPORT
 private FzTupleEntity GetSelectedAttributes(FzTupleEntity resultTuple)
 {
     FzTupleEntity r = new FzTupleEntity();
     for (int i = 0; i < _index.Count; i++)
     {
         for (int j = 0; j < resultTuple.ValuesOnPerRow.Count; j++)
         {
             if (_index[i] == j)
             {
                 r.ValuesOnPerRow.Add(resultTuple.ValuesOnPerRow[j]);
                 break;
             }
         }
     }
     r.ValuesOnPerRow.Add(resultTuple.ValuesOnPerRow[resultTuple.ValuesOnPerRow.Count - 1]);
     return r;
 }
Ejemplo n.º 9
0
        private void SaveTuples(FzRelationEntity currentRelation)
        {
            int nRow, nCol;
            nRow = GridViewData.Rows.Count - 1;
            nCol = GridViewData.Columns.Count;

            if (GridViewData.Rows.Count <= 1) return;
            GridViewData.CurrentCell = GridViewData.Rows[nRow].Cells[0];

            currentRelation.Tuples.Clear();

            for (int i = 0; i < nRow; i++)
            {
                List<Object> objs = new List<object>();

                for (int j = 0; j < nCol; j++)
                {
                    if (GridViewData.Rows[i].Cells[j].Value == null)
                    {
                        throw new Exception("Value cell is empty!");
                    }

                    objs.Add(GridViewData.Rows[i].Cells[j].Value);
                }

                FzTupleEntity tuple = new FzTupleEntity()
            { ValuesOnPerRow = objs };
                currentRelation.Tuples.Add(tuple);
            }
        }
Ejemplo n.º 10
0
        private void ExecutingQuery()
        {
            try
            {
                PrepareQuery();
                String query = QueryPL.StandardizeQuery(txtQuery.Text.Trim());
                String messagefirst = QueryPL.CheckSyntaxfirst(query);
                if (messagefirst != "")
                {
                    ShowMessage(messagefirst, Color.Red);
                    return;
                }
                FdbEntity newFdb = new FdbEntity() { Relations = fdbEntity.Relations, Schemes = fdbEntity.Schemes };

                if (query.Contains("descartes"))
                {

                    _errorMessage = null;
                    _error = false;
                    rlAB = new FzRelationEntity();
                    atAB = new List<FzAttributeEntity>();
                    _selectedAttributesAB = new List<FzAttributeEntity>();
                    _conditionTextAB = String.Empty;
                    _selectedAttributeTextsAB = null;
                    _indexAB = new List<int>() ;

                    String relationA = GetRelationTextsA(query);
                    String queryA = "select * from " + relationA;
                    QueryPL.StandardizeQuery(queryA);
                    String message = QueryPL.CheckSyntax(queryA);
                    if (message != "")
                    {
                        ShowMessage(message, Color.Red);
                        return;
                    }
                    QueryExcutetionBLL excutetionA = null;
                    excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);

                    String relationB = GetRelationB(query);
                    String queryB = "select * from " + relationB;
                    QueryPL.StandardizeQuery(queryB);
                    QueryExcutetionBLL excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                    FzRelationEntity resultA = null;
                    resultA = excutetionA.ExecuteQuery();
                    if (excutetionA.Error)
                    {
                        ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                    }
                    FzRelationEntity resultB = null;
                    resultB = excutetionB.ExecuteQuery();
                    if (excutetionB.Error)
                    {
                        ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                    }
                    if (resultA != null && resultB != null)
                    {
                        if (query.Contains("descartes"))
                        {
                            int[] arrAB = new int[resultA.Scheme.Attributes.Count];
                            int same_att = 0;
                            int a = 0;
                            bool valueAB;
                            foreach (FzAttributeEntity att1 in resultA.Scheme.Attributes)
                            {
                                a++;
                                valueAB = false;
                                foreach (FzAttributeEntity att2 in resultB.Scheme.Attributes)
                                {
                                    if ((att1.AttributeName.Equals(att2.AttributeName)) && (a < resultA.Scheme.Attributes.Count))
                                    {
                                        valueAB = true;
                                        same_att++;

                                    }

                                }
                                if (valueAB == true)
                                {
                                    arrAB[a - 1] = 1;
                                }
                                else
                                {
                                    arrAB[a - 1] = 0;
                                }
                            }
                            if (same_att > 0)
                            {
                                ShowMessage("Between two relations, there mustn't be the same attribute", Color.Red);
                                return;
                            }
                            else
                            {
                                int ncol1 = resultA.Scheme.Attributes.Count;
                                int nrow1 = resultA.Tuples.Count;
                                int ncol2 = resultB.Scheme.Attributes.Count;
                                int nrow2 = resultB.Tuples.Count;
                                int m = 0;

                                FzTupleEntity tpl1;
                                FzTupleEntity tpl2;
                                foreach (FzAttributeEntity attribute2 in resultB.Scheme.Attributes)
                                {
                                    if (m == 0)
                                    {
                                        foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                        {

                                            if (m < ncol1 - 1)
                                            {
                                                atAB.Add(attribute1);
                                                m++;

                                            }
                                        }
                                    }

                                    atAB.Add(attribute2);
                                    m++;

                                }

                                rlAB.Scheme.Attributes = atAB;
                                int r = 0;

                                for (int i = 0; i < nrow1; i++)
                                {
                                    tpl1 = resultA.Tuples[i];
                                    for (int j = 0; j < nrow2; j++)
                                    {
                                        List<Object> objs = new List<object>();

                                        tpl2 = resultB.Tuples[j];
                                        int k = 0;
                                        foreach (Object value1 in tpl1.ValuesOnPerRow)
                                        {

                                            if (k < ncol1 - 1)
                                            {
                                                objs.Add(value1.ToString());
                                                k++;

                                            }

                                        }
                                        foreach (Object value2 in tpl2.ValuesOnPerRow)
                                        {
                                            if ((k >= ncol1 - 1) && (k < m - 1))
                                            {
                                                objs.Add(value2.ToString());
                                                k++;
                                            }
                                            if (k == m - 1 && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) <= Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                            {
                                                objs.Add(tpl1.ValuesOnPerRow[ncol1 - 1]);
                                                k++;
                                            }
                                            if (k == m - 1 && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) > Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                            {
                                                objs.Add(tpl2.ValuesOnPerRow[ncol2 - 1]);
                                                k++;
                                            }
                                        }

                                        FzTupleEntity tplab = new FzTupleEntity() { ValuesOnPerRow = objs };
                                        rlAB.Tuples.Add(tplab);
                                        r++;

                                    }

                                }
                                String queryAB = GetQueryAB(query) + " from " + rlAB.RelationName;
                                QueryPL.StandardizeQuery(queryAB);
                                QueryExcutetionBLL excutetionAB = new QueryExcutetionBLL(queryAB.ToLower(), newFdb.Relations);
                                FzRelationEntity resultAB = new FzRelationEntity();
                                this._selectedAttributeTextsAB = GetAttributeTextsAB(query);
                                this._conditionTextAB = GetConditionText(query);
                                if (_conditionTextAB != String.Empty)
                                    this._conditionTextAB = AddParenthesis(this._conditionTextAB);
                                this.GetSelectedAttr();
                                if (this._error) throw new Exception(this._errorMessage);

                                _errorMessage = ExistsAttribute();
                                if (ErrorMessage != "") { this.Error = true; throw new Exception(_errorMessage); }
                                if (query.Contains("where"))
                                {
                                    List<Item> items = FormatCondition(this._conditionTextAB);
                                    //Check fuzzy set and object here
                                    this.ErrorMessage = ExistsFuzzySet(items);
                                    if (ErrorMessage != "")
                                    {

                                        ShowMessage(ErrorMessage, Color.Red); return;
                                    }

                                    QueryConditionBLL1 condition = new QueryConditionBLL1(items, this.rlAB);
                                    resultAB.Scheme.Attributes = this._selectedAttributesAB;

                                    foreach (FzTupleEntity tuple in this.rlAB.Tuples)
                                    {
                                        if (condition.Satisfy(items, tuple))
                                        {
                                            if (this._selectedAttributeTextsAB != null)
                                                resultAB.Tuples.Add(GetSelectedAttributes(condition.ResultTuple));
                                            else
                                                resultAB.Tuples.Add(condition.ResultTuple);
                                        }
                                    }
                                }
                                else// Select all tuples
                                {
                                    resultAB.Scheme.Attributes = this._selectedAttributesAB;
                                    resultAB.RelationName = this.rlAB.RelationName;

                                    if (this._selectedAttributeTextsAB != null)
                                    {
                                        foreach (var item in this.rlAB.Tuples)
                                            resultAB.Tuples.Add(GetSelectedAttributes(item));
                                    }
                                    else
                                    {
                                        foreach (var item in this.rlAB.Tuples)
                                            resultAB.Tuples.Add(item);
                                    }
                                }

                                if (resultAB != null)
                                {
                                    foreach (FzAttributeEntity attribute in resultAB.Scheme.Attributes)
                                        GridViewResult.Columns.Add(attribute.AttributeName, attribute.AttributeName);

                                    int j, i = -1;
                                    foreach (FzTupleEntity tuple in resultAB.Tuples)
                                    {
                                        GridViewResult.Rows.Add();
                                        i++; j = -1;
                                        foreach (Object value in tuple.ValuesOnPerRow)
                                            GridViewResult.Rows[i].Cells[++j].Value = value.ToString();
                                    }

                                    xtraTabQueryResult.SelectedTabPageIndex = 0;
                                    //txtMessage.Text = "There are "+ GridViewResult.RowCount+" row(s) affected";
                                }
                                else
                                {
                                    txtMessage.Text = "There is no relation satisfy the condition";
                                    xtraTabQueryResult.SelectedTabPageIndex = 1;

                                }
                            }

                        }
                        else
                        {
                            txtMessage.Text = "There is no relation satisfy the condition";
                            xtraTabQueryResult.SelectedTabPageIndex = 1;

                        }
                        siStatus.Caption = "Ready";
                        txtMessage.ForeColor = Color.Black;
                        txtMessage.Text = "There are " + GridViewResult.RowCount + " row(s) affected";

                    }

                }
                else
                {

                    if (query.Contains("natural join"))
                    {
                        _errorMessage = null;
                        _error = false;
                        rlAB = new FzRelationEntity();
                        atAB = new List<FzAttributeEntity>();
                        _selectedAttributesAB = new List<FzAttributeEntity>();
                        _conditionTextAB = String.Empty;
                        _selectedAttributeTextsAB = null;
                        _indexAB = new List<int>();
                        String relationA = GetRelationTextsA(query);
                        String queryA = "select * from " + relationA;
                        QueryPL.StandardizeQuery(queryA);
                        String message = QueryPL.CheckSyntax(queryA);
                        if (message != "")
                        {
                            ShowMessage(message, Color.Red);
                            return;
                        }
                        QueryExcutetionBLL excutetionA = null;
                        excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);

                        String relationB = GetRelationB(query);
                        String queryB = "select * from " + relationB;
                        QueryPL.StandardizeQuery(queryB);
                        QueryExcutetionBLL excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                        FzRelationEntity resultA = null;
                        resultA = excutetionA.ExecuteQuery();
                        if (excutetionA.Error)
                        {
                            ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                        }
                        FzRelationEntity resultB = null;
                        resultB = excutetionB.ExecuteQuery();
                        if (excutetionB.Error)
                        {
                            ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                        }

                        if (resultA != null && resultB != null)
                        {
                            if (query.Contains("natural join"))
                            {

                                int ncol1 = resultA.Scheme.Attributes.Count;
                                int nrow1 = resultA.Tuples.Count;
                                int ncol2 = resultB.Scheme.Attributes.Count;
                                int nrow2 = resultB.Tuples.Count;
                                int m = 0;
                                int[] arr1 = new int[ncol1];
                                bool same;
                                int stt = 0;
                                int stt2;
                                int dem = 0;
                                int same1 = 0;
                                int same2 = 0;
                                foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                {

                                    same = false;
                                    stt++;
                                    stt2 = 0;
                                    foreach (FzAttributeEntity attribute2 in resultB.Scheme.Attributes)
                                    {
                                        stt2++;
                                        if ((attribute1.AttributeName.ToString() == attribute2.AttributeName.ToString()))
                                        {
                                            dem++;
                                            same = true;
                                            arr1[stt - 1] = 1;
                                            if (dem == 1)
                                            {
                                                same1 = stt;
                                                same2 = stt2;
                                            }

                                        }

                                    }
                                    if (same == false && (m < ncol1 - 2))
                                    {
                                        atAB.Add(attribute1);
                                        m++;
                                        arr1[stt - 1] = 0;
                                    }
                                    if (m == ncol1 - 2)
                                    {
                                        foreach (FzAttributeEntity attribute2 in resultB.Scheme.Attributes)
                                        {
                                            atAB.Add(attribute2);
                                            m++;
                                        }
                                    }
                                }
                                rlAB.Scheme.Attributes = atAB;

                                int row = 0;
                                if (dem != 2)
                                {
                                    ShowMessage("Between two ralations, there is only one the same attribute", Color.Red);
                                    return;
                                }
                                else
                                {

                                    FzTupleEntity tpl1;
                                    FzTupleEntity tpl2;
                                    for (int i = 0; i < nrow1; i++)
                                    {
                                        tpl1 = resultA.Tuples[i];
                                        for (int j = 0; j < nrow2; j++)
                                        {
                                            tpl2 = resultB.Tuples[j];
                                            if (tpl1.ValuesOnPerRow[same1 - 1].ToString() == tpl2.ValuesOnPerRow[same2 - 1].ToString())
                                            {
                                                List<Object> objs = new List<object>();

                                                int k = 0;
                                                int stt_cell;
                                                stt_cell = 0;
                                                foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                {
                                                    stt_cell++;

                                                    if ((k < ncol1 - 2) && (arr1[stt_cell - 1] == 0))
                                                    {
                                                        objs.Add(value1.ToString());
                                                        k++;
                                                    }

                                                }
                                                foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                {
                                                    if ((k >= (ncol1 - 2)) && (k < m - 1))
                                                    {
                                                        objs.Add(value2.ToString());
                                                        k++;
                                                    }

                                                }
                                                if ((k == m - 1) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) >= Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                {

                                                    objs.Add(tpl1.ValuesOnPerRow[ncol1 - 1]);
                                                }
                                                else
                                                {
                                                    if ((k == m - 1) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) < Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                    {
                                                        objs.Add(tpl2.ValuesOnPerRow[ncol2 - 1]);
                                                    }

                                                }
                                                FzTupleEntity tplab = new FzTupleEntity() { ValuesOnPerRow = objs };
                                                rlAB.Tuples.Add(tplab);
                                                row++;

                                            }
                                        }
                                    }

                                    String queryAB = GetQueryAB(query) + " from " + rlAB.RelationName;
                                    QueryPL.StandardizeQuery(queryAB);
                                    QueryExcutetionBLL excutetionAB = new QueryExcutetionBLL(queryAB.ToLower(), newFdb.Relations);
                                    FzRelationEntity resultAB = new FzRelationEntity();
                                    this._selectedAttributeTextsAB = GetAttributeTextsAB(query);
                                    this._conditionTextAB = GetConditionText(query);
                                    if (_conditionTextAB != String.Empty)
                                        this._conditionTextAB = AddParenthesis(this._conditionTextAB);
                                    this.GetSelectedAttr();
                                    if (this._error) throw new Exception(this._errorMessage);

                                    _errorMessage = ExistsAttribute();
                                    if (ErrorMessage != "") { this.Error = true; throw new Exception(_errorMessage); }
                                    if (query.Contains("where"))
                                    {
                                        List<Item> items = FormatCondition(this._conditionTextAB);
                                        //Check fuzzy set and object here
                                        this.ErrorMessage = ExistsFuzzySet(items);
                                        if (ErrorMessage != "")
                                        {

                                            ShowMessage(ErrorMessage, Color.Red); return;
                                        }

                                        QueryConditionBLL1 condition = new QueryConditionBLL1(items, this.rlAB);
                                        resultAB.Scheme.Attributes = this._selectedAttributesAB;

                                        foreach (FzTupleEntity tuple in this.rlAB.Tuples)
                                        {
                                            if (condition.Satisfy(items, tuple))
                                            {
                                                if (this._selectedAttributeTextsAB != null)
                                                    resultAB.Tuples.Add(GetSelectedAttributes(condition.ResultTuple));
                                                else
                                                    resultAB.Tuples.Add(condition.ResultTuple);
                                            }
                                        }
                                    }
                                    else// Select all tuples
                                    {
                                        resultAB.Scheme.Attributes = this._selectedAttributesAB;
                                        resultAB.RelationName = this.rlAB.RelationName;

                                        if (this._selectedAttributeTextsAB != null)
                                        {
                                            foreach (var item in this.rlAB.Tuples)
                                                resultAB.Tuples.Add(GetSelectedAttributes(item));
                                        }
                                        else
                                        {
                                            foreach (var item in this.rlAB.Tuples)
                                                resultAB.Tuples.Add(item);
                                        }
                                    }

                                    if (resultAB != null)
                                    {
                                        foreach (FzAttributeEntity attribute in resultAB.Scheme.Attributes)
                                            GridViewResult.Columns.Add(attribute.AttributeName, attribute.AttributeName);

                                        int j, i = -1;
                                        foreach (FzTupleEntity tuple in resultAB.Tuples)
                                        {
                                            GridViewResult.Rows.Add();
                                            i++; j = -1;
                                            foreach (Object value in tuple.ValuesOnPerRow)
                                                GridViewResult.Rows[i].Cells[++j].Value = value.ToString();
                                        }

                                        xtraTabQueryResult.SelectedTabPageIndex = 0;
                                        //txtMessage.Text = "There are " + GridViewResult.RowCount + " row(s) affected";
                                    }
                                    else
                                    {
                                        txtMessage.Text = "There is no relation satisfy the condition";
                                        xtraTabQueryResult.SelectedTabPageIndex = 1;

                                    }

                                }
                            }
                            else
                            {
                                txtMessage.Text = "There is no relation satisfy the condition";
                                xtraTabQueryResult.SelectedTabPageIndex = 1;

                            }
                            siStatus.Caption = "Ready";
                            txtMessage.ForeColor = Color.Black;
                            txtMessage.Text = GridViewResult.RowCount + " row(s) affected";
                        }
                    }
                    //
                    else
                    {
                        if (query.Contains("union") && (!query.Contains("union all")))
                        {
                            String queryA = null;
                            queryA = GetQueryA(query);
                            QueryPL.StandardizeQuery(queryA);
                            String messageA = null;
                            messageA = QueryPL.CheckSyntax(queryA);
                            if (messageA != "")
                            {
                                ShowMessage(messageA, Color.Red);
                                return;
                            }
                            String relationB = GetQueryTextsB(query);
                            String queryB = relationB;
                            QueryPL.StandardizeQuery(queryB);
                            String messageB = null;
                            messageB = QueryPL.CheckSyntax(queryA);
                            if (messageB != "")
                            {
                                ShowMessage(messageB, Color.Red);
                                return;
                            }
                            QueryExcutetionBLL excutetionA = null;
                            excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);
                            QueryExcutetionBLL excutetionB = null;
                            excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                            FzRelationEntity resultA = null;
                            resultA = excutetionA.ExecuteQuery();
                            if (excutetionA.Error)
                            {
                                ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                            }
                            FzRelationEntity resultB = null;
                            resultB = excutetionB.ExecuteQuery();
                            if (excutetionB.Error)
                            {
                                ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                            }
                            if (resultA != null && resultB != null)
                            {
                                if (query.Contains("union") && (!query.Contains("union all")))
                                {
                                    int same_att = 0;
                                    int a = 0;
                                    foreach (FzAttributeEntity att1 in resultA.Scheme.Attributes)
                                    {
                                        a++;
                                        int b = 0;
                                        foreach (FzAttributeEntity att2 in resultB.Scheme.Attributes)
                                        {
                                            b++;
                                            if (att1.AttributeName.Equals(att2.AttributeName) && (a == b))
                                            {
                                                same_att++;
                                            }
                                        }
                                    }
                                    if (same_att != resultA.Scheme.Attributes.Count)
                                    {
                                        ShowMessage("The number of columns have to be same, data types have to be same and they have to be in same order.", Color.Red);
                                        return;
                                    }
                                    else
                                    {
                                        int ncol1 = resultA.Scheme.Attributes.Count;
                                        int nrow1 = resultA.Tuples.Count;
                                        int ncol2 = resultB.Scheme.Attributes.Count;
                                        int nrow2 = resultB.Tuples.Count;
                                        int m = 0;

                                        foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                        {

                                            GridViewResult.Columns.Add(attribute1.AttributeName, attribute1.AttributeName);
                                            m++;
                                        }

                                        FzTupleEntity tpl1;
                                        FzTupleEntity tpl2;
                                        int r;
                                        r = -1;
                                        for (int i = 0; i < nrow1; i++)
                                        {
                                            tpl1 = resultA.Tuples[i];

                                            int stt = -1;
                                            Boolean valuecheck = false;
                                            for (int j = 0; j < nrow2; j++)
                                                {

                                                   tpl2 = resultB.Tuples[j];
                                                   if (tpl1.ValuesOnPerRow[0].ToString() == tpl2.ValuesOnPerRow[0].ToString())
                                                   {
                                                       valuecheck = true;
                                                   }
                                                   if (r < nrow2-1)
                                                   {
                                                       r++;
                                                       int k2 = -1;
                                                       GridViewResult.Rows.Add();
                                                       foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                       {
                                                           if(k2<m-2)
                                                           {
                                                               GridViewResult.Rows[j].Cells[++k2].Value = value2.ToString();
                                                           }
                                                           if(tpl1.ValuesOnPerRow[0].ToString() != tpl2.ValuesOnPerRow[0].ToString())
                                                           {
                                                               GridViewResult.Rows[j].Cells[m-1].Value = value2.ToString();
                                                           }
                                                       }

                                                    }
                                                   if ((tpl1.ValuesOnPerRow[0].ToString() == tpl2.ValuesOnPerRow[0].ToString()) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) < Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                   {
                                                       GridViewResult.Rows[j].Cells[m - 1].Value = tpl1.ValuesOnPerRow[ncol1 - 1];

                                                   }
                                                   if ((tpl1.ValuesOnPerRow[0].ToString() == tpl2.ValuesOnPerRow[0].ToString()) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) >= Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                   {
                                                       GridViewResult.Rows[j].Cells[m - 1].Value = tpl2.ValuesOnPerRow[ncol2 - 1];

                                                   }

                                            }

                                            if (valuecheck == false)
                                            {
                                                 r++;
                                                int k = -1;
                                                GridViewResult.Rows.Add();
                                                foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                {
                                                   GridViewResult.Rows[r].Cells[++k].Value = value1.ToString();
                                                }
                                            }
                                        }
                                        xtraTabQueryResult.SelectedTabPageIndex = 0;
                                    }

                                }
                                else
                                {
                                    txtMessage.Text = "There is no relation satisfy the condition";
                                    xtraTabQueryResult.SelectedTabPageIndex = 1;

                                }
                                siStatus.Caption = "Ready";
                                txtMessage.ForeColor = Color.Black;
                                txtMessage.Text = GridViewResult.RowCount + " row(s) affected";
                            }
                        }
                        else
                        {
                            if (query.Contains("intersect"))
                            {
                                String queryA = null;
                                queryA = GetQueryA(query);
                                QueryPL.StandardizeQuery(queryA);
                                String messageA = null;
                                messageA = QueryPL.CheckSyntax(queryA);
                                if (messageA != "")
                                {
                                    ShowMessage(messageA, Color.Red);
                                    return;
                                }
                                String relationB = GetQueryTextsB(query);
                                String queryB = relationB;
                                QueryPL.StandardizeQuery(queryB);
                                String messageB = null;
                                messageB = QueryPL.CheckSyntax(queryA);
                                if (messageB != "")
                                {
                                    ShowMessage(messageB, Color.Red);
                                    return;
                                }
                                QueryExcutetionBLL excutetionA = null;
                                excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);
                                QueryExcutetionBLL excutetionB = null;
                                excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                                FzRelationEntity resultA = null;
                                resultA = excutetionA.ExecuteQuery();
                                if (excutetionA.Error)
                                {
                                    ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                                }
                                FzRelationEntity resultB = null;
                                resultB = excutetionB.ExecuteQuery();
                                if (excutetionB.Error)
                                {
                                    ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                                }
                                if (resultA != null && resultB != null)
                                {
                                    if (query.Contains("intersect"))
                                    {
                                        int same_att = 0;
                                        int a = 0;
                                        foreach (FzAttributeEntity att1 in resultA.Scheme.Attributes)
                                        {
                                            a++;
                                            int b = 0;
                                            foreach (FzAttributeEntity att2 in resultB.Scheme.Attributes)
                                            {
                                                b++;
                                                if (att1.AttributeName.Equals(att2.AttributeName) && (a == b))
                                                {
                                                    same_att++;
                                                }
                                            }
                                        }
                                        if (same_att != resultA.Scheme.Attributes.Count)
                                        {
                                            ShowMessage("The number of columns have to be same, data types have to be same and they have to be in same order.", Color.Red);
                                            return;
                                        }
                                        else
                                        {
                                            int ncol1 = resultA.Scheme.Attributes.Count;
                                            int nrow1 = resultA.Tuples.Count;
                                            int ncol2 = resultB.Scheme.Attributes.Count;
                                            int nrow2 = resultB.Tuples.Count;
                                            int m = 0;
                                            int row = -1;
                                            //option1
                                            foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                            {
                                                GridViewResult.Columns.Add(attribute1.AttributeName, attribute1.AttributeName);
                                                m++;
                                            }

                                            FzTupleEntity tpl1;
                                            FzTupleEntity tpl2;

                                            for (int i = 0; i < nrow1; i++)
                                            {
                                                tpl1 = resultA.Tuples[i];
                                                    String valueCheck = null;
                                                    for (int j = 0; j < nrow2; j++)
                                                    {
                                                        tpl2 = resultB.Tuples[j];
                                                        foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                        {
                                                            if ((tpl1.ValuesOnPerRow[0].ToString() == tpl2.ValuesOnPerRow[0].ToString()) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) > Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                            {
                                                                valueCheck = tpl2.ValuesOnPerRow[ncol2 - 1].ToString();
                                                            }
                                                            if ((tpl1.ValuesOnPerRow[0].ToString() == tpl2.ValuesOnPerRow[0].ToString()) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) <= Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                            {
                                                                valueCheck = tpl1.ValuesOnPerRow[ncol2 - 1].ToString();
                                                            }

                                                        }
                                                    }
                                                    if (valueCheck != null)
                                                    {
                                                        GridViewResult.Rows.Add();
                                                        int k = -1;
                                                        row++;
                                                        foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                        {

                                                            if (k < m - 2)
                                                            {
                                                                GridViewResult.Rows[i].Cells[++k].Value = value1.ToString();

                                                            }
                                                            if (k == m - 2)
                                                            {
                                                                GridViewResult.Rows[i].Cells[++k].Value = valueCheck;

                                                            }
                                                         }
                                                    }

                                               }
                                            xtraTabQueryResult.SelectedTabPageIndex = 0;
                                        }

                                    }
                                    else
                                    {
                                        txtMessage.Text = "There is no relation satisfy the condition";
                                        xtraTabQueryResult.SelectedTabPageIndex = 1;

                                    }
                                    siStatus.Caption = "Ready";
                                    txtMessage.ForeColor = Color.Black;
                                    txtMessage.Text = GridViewResult.RowCount + " row(s) affected";
                                }
                            }
                            else
                            {

                                if (query.Contains("except"))
                                {
                                    String queryA = null;
                                    queryA = GetQueryA(query);
                                    QueryPL.StandardizeQuery(queryA);
                                    String messageA = null;
                                    messageA = QueryPL.CheckSyntax(queryA);
                                    if (messageA != "")
                                    {
                                        ShowMessage(messageA, Color.Red);
                                        return;
                                    }
                                    String relationB = GetQueryTextsB(query);
                                    String queryB = relationB;
                                    QueryPL.StandardizeQuery(queryB);
                                    String messageB = null;
                                    messageB = QueryPL.CheckSyntax(queryA);
                                    if (messageB != "")
                                    {
                                        ShowMessage(messageB, Color.Red);
                                        return;
                                    }
                                    QueryExcutetionBLL excutetionA = null;
                                    excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);
                                    QueryExcutetionBLL excutetionB = null;
                                    excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                                    FzRelationEntity resultA = null;
                                    resultA = excutetionA.ExecuteQuery();
                                    if (excutetionA.Error)
                                    {
                                        ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                                    }
                                    FzRelationEntity resultB = null;
                                    resultB = excutetionB.ExecuteQuery();
                                    if (excutetionB.Error)
                                    {
                                        ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                                    }
                                    if (resultA != null && resultB != null)
                                    {
                                        if (query.Contains("except"))
                                        {
                                            int same_att = 0;
                                            int a = 0;
                                            foreach (FzAttributeEntity att1 in resultA.Scheme.Attributes)
                                            {
                                                a++;
                                                int b = 0;
                                                foreach (FzAttributeEntity att2 in resultB.Scheme.Attributes)
                                                {
                                                    b++;
                                                    if (att1.AttributeName.Equals(att2.AttributeName) && (a == b))
                                                    {
                                                        same_att++;
                                                    }
                                                }
                                            }
                                            if (same_att != resultA.Scheme.Attributes.Count)
                                            {
                                                ShowMessage("The number of columns have to be same, data types have to be same and they have to be in same order.", Color.Red);
                                                return;
                                            }
                                            else
                                            {
                                                int ncol1 = resultA.Scheme.Attributes.Count;
                                                int nrow1 = resultA.Tuples.Count;
                                                int ncol2 = resultB.Scheme.Attributes.Count;
                                                int nrow2 = resultB.Tuples.Count;
                                                int m = 0;

                                                foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                                {

                                                    GridViewResult.Columns.Add(attribute1.AttributeName, attribute1.AttributeName);
                                                    m++;
                                                }

                                                FzTupleEntity tpl1;
                                                FzTupleEntity tpl2;

                                                for (int i = 0; i < nrow1; i++)
                                                {
                                                    tpl1 = resultA.Tuples[i];

                                                    GridViewResult.Rows.Add();
                                                    int k = -1;
                                                    foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                    {
                                                        String valueCheck = null;
                                                        for (int j = 0; j < nrow2; j++)
                                                        {
                                                            tpl2 = resultB.Tuples[j];
                                                            foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                            {
                                                                if ((tpl1.ValuesOnPerRow[0].ToString() == tpl2.ValuesOnPerRow[0].ToString()) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) <= 1 - Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                                {
                                                                    valueCheck = tpl1.ValuesOnPerRow[ncol1 - 1].ToString();
                                                                }
                                                                if ((tpl1.ValuesOnPerRow[0].ToString() == tpl2.ValuesOnPerRow[0].ToString()) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) > 1 - Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                                {
                                                                    valueCheck = Convert.ToString(1 - Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1]));
                                                                }

                                                            }
                                                        }
                                                        if (valueCheck == null)
                                                        {
                                                            GridViewResult.Rows[i].Cells[++k].Value = value1.ToString();

                                                        }
                                                        if (valueCheck != null && k < m - 2)
                                                        {
                                                            GridViewResult.Rows[i].Cells[++k].Value = value1.ToString();

                                                        }
                                                        if (valueCheck != null && (k == m - 2))
                                                        {
                                                            GridViewResult.Rows[i].Cells[++k].Value = valueCheck;

                                                        }

                                                    }

                                                }
                                                xtraTabQueryResult.SelectedTabPageIndex = 0;
                                            }

                                        }
                                        else
                                        {
                                            txtMessage.Text = "There is no relation satisfy the condition";
                                            xtraTabQueryResult.SelectedTabPageIndex = 1;

                                        }
                                        siStatus.Caption = "Ready";
                                        txtMessage.ForeColor = Color.Black;
                                        txtMessage.Text = GridViewResult.RowCount + " row(s) affected";
                                    }
                                }
                                else
                                {
                                    if (query.Contains("union all"))
                                    {
                                        String queryA = null;
                                        queryA = GetQueryA(query);
                                        QueryPL.StandardizeQuery(queryA);
                                        String messageA = null;
                                        messageA = QueryPL.CheckSyntax(queryA);
                                        if (messageA != "")
                                        {
                                            ShowMessage(messageA, Color.Red);
                                            return;
                                        }
                                        String relationB = GetQueryTextsB(query);
                                        String queryB = relationB;
                                        QueryPL.StandardizeQuery(queryB);
                                        String messageB = null;
                                        messageB = QueryPL.CheckSyntax(queryA);
                                        if (messageB != "")
                                        {
                                            ShowMessage(messageB, Color.Red);
                                            return;
                                        }
                                        QueryExcutetionBLL excutetionA = null;
                                        excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);
                                        QueryExcutetionBLL excutetionB = null;
                                        excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                                        FzRelationEntity resultA = null;
                                        resultA = excutetionA.ExecuteQuery();
                                        if (excutetionA.Error)
                                        {
                                            ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                                        }
                                        FzRelationEntity resultB = null;
                                        resultB = excutetionB.ExecuteQuery();
                                        if (excutetionB.Error)
                                        {
                                            ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                                        }
                                        if (resultA != null && resultB != null)
                                        {
                                            if (query.Contains("union all"))
                                            {
                                                int same_att = 0;
                                                int a = 0;
                                                foreach (FzAttributeEntity att1 in resultA.Scheme.Attributes)
                                                {
                                                    a++;
                                                    int b = 0;
                                                    foreach (FzAttributeEntity att2 in resultB.Scheme.Attributes)
                                                    {
                                                        b++;
                                                        if (att1.AttributeName.Equals(att2.AttributeName) && (a == b))
                                                        {
                                                            same_att++;
                                                        }
                                                    }
                                                }
                                                if (same_att != resultA.Scheme.Attributes.Count)
                                                {
                                                    ShowMessage("The number of columns have to be same, data types have to be same and they have to be in same order.", Color.Red);
                                                    return;
                                                }
                                                else
                                                {
                                                    int ncol1 = resultA.Scheme.Attributes.Count;
                                                    int nrow1 = resultA.Tuples.Count;
                                                    int ncol2 = resultB.Scheme.Attributes.Count;
                                                    int nrow2 = resultB.Tuples.Count;
                                                    int m = 0;

                                                    foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                                    {

                                                        GridViewResult.Columns.Add(attribute1.AttributeName, attribute1.AttributeName);
                                                        m++;
                                                    }

                                                    FzTupleEntity tpl1;
                                                    FzTupleEntity tpl2;
                                                    int r;
                                                    r = -1;
                                                    for (int i = 0; i < nrow1; i++)
                                                    {
                                                        tpl1 = resultA.Tuples[i];
                                                        for (int j = 0; j < nrow2; j++)
                                                        {
                                                            tpl2 = resultB.Tuples[j];
                                                            if (r < nrow2 - 1)
                                                            {
                                                                r++;
                                                                int k2 = -1;
                                                                GridViewResult.Rows.Add();
                                                                foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                                {
                                                                        GridViewResult.Rows[j].Cells[++k2].Value = value2.ToString();
                                                                }
                                                            }
                                                          }
                                                            r++;
                                                            int k = -1;
                                                            GridViewResult.Rows.Add();
                                                            foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                            {
                                                                GridViewResult.Rows[r].Cells[++k].Value = value1.ToString();
                                                            }
                                                        }
                                                    xtraTabQueryResult.SelectedTabPageIndex = 0;
                                                }
                                              }
                                            else
                                            {
                                                txtMessage.Text = "There is no relation satisfy the condition";
                                                xtraTabQueryResult.SelectedTabPageIndex = 1;

                                            }
                                            siStatus.Caption = "Ready";
                                            txtMessage.ForeColor = Color.Black;
                                            txtMessage.Text = GridViewResult.RowCount + " row(s) affected";
                                        }
                                    }
                                    else
                                    {
                    if (query.Contains("left join"))
                    {
                        _errorMessage = null;
                        _error = false;
                        rlAB = new FzRelationEntity();
                        atAB = new List<FzAttributeEntity>();
                        _selectedAttributesAB = new List<FzAttributeEntity>();
                        _conditionTextAB = String.Empty;
                        _selectedAttributeTextsAB = null;
                        _indexAB = new List<int>();
                        String relationA = GetRelationTextsA(query);
                        String queryA = "select * from " + relationA;
                        QueryPL.StandardizeQuery(queryA);
                        String message = QueryPL.CheckSyntax(queryA);
                        if (message != "")
                        {
                            ShowMessage(message, Color.Red);
                            return;
                        }
                        QueryExcutetionBLL excutetionA = null;
                        excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);

                        String relationB = GetRelationB(query);
                        String queryB = "select * from " + relationB;
                        QueryPL.StandardizeQuery(queryB);
                        QueryExcutetionBLL excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                        FzRelationEntity resultA = null;
                        resultA = excutetionA.ExecuteQuery();
                        if (excutetionA.Error)
                        {
                            ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                        }
                        FzRelationEntity resultB = null;
                        resultB = excutetionB.ExecuteQuery();
                        if (excutetionB.Error)
                        {
                            ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                        }

                        if (resultA != null && resultB != null)
                        {
                            if (query.Contains("left join"))
                            {

                                int ncol1 = resultA.Scheme.Attributes.Count;
                                int nrow1 = resultA.Tuples.Count;
                                int ncol2 = resultB.Scheme.Attributes.Count;
                                int nrow2 = resultB.Tuples.Count;
                                int m = 0;
                                int[] arr1 = new int[ncol1];
                                bool same;
                                int stt = 0;
                                int stt2;
                                int dem = 0;
                                int same1 = 0;
                                int same2 = 0;
                                foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                {

                                    same = false;
                                    stt++;
                                    stt2 = 0;
                                    foreach (FzAttributeEntity attribute2 in resultB.Scheme.Attributes)
                                    {
                                        stt2++;
                                        if ((attribute1.AttributeName.ToString() == attribute2.AttributeName.ToString()))
                                        {
                                            dem++;
                                            same = true;
                                            arr1[stt - 1] = 1;
                                            if (dem == 1)
                                            {
                                                same1 = stt;
                                                same2 = stt2;
                                            }
                                        }

                                    }
                                    if (same == false && (m < ncol1 - 2))
                                    {
                                        atAB.Add(attribute1);
                                        m++;
                                        arr1[stt - 1] = 0;
                                    }
                                    if (m == ncol1 - 2)
                                    {
                                        foreach (FzAttributeEntity attribute2 in resultB.Scheme.Attributes)
                                        {
                                            atAB.Add(attribute2);
                                            m++;
                                        }
                                    }
                                }
                                rlAB.Scheme.Attributes = atAB;

                                int row = 0;
                                if (dem != 2)
                                {
                                    ShowMessage("Between two ralations, there is only one the same attribute", Color.Red);
                                    return;
                                }
                                else
                                {

                                    FzTupleEntity tpl1;
                                    FzTupleEntity tpl2;
                                    bool valuecheck ;
                                    for (int i = 0; i < nrow1; i++)
                                    {
                                        tpl1 = resultA.Tuples[i];
                                        valuecheck = false;
                                        for (int j = 0; j < nrow2; j++)
                                        {
                                            tpl2 = resultB.Tuples[j];
                                            if (tpl1.ValuesOnPerRow[same1 - 1].ToString() == tpl2.ValuesOnPerRow[same2 - 1].ToString())
                                            {
                                                valuecheck = true;
                                                List<Object> objs = new List<object>();
                                                int k = 0;
                                                int stt_cell;
                                                stt_cell = 0;
                                                foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                {
                                                    stt_cell++;

                                                    if ((k < ncol1 - 2) && (arr1[stt_cell - 1] == 0))
                                                    {
                                                        objs.Add(value1.ToString());
                                                        k++;
                                                    }

                                                }
                                                foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                {
                                                    if ((k >= (ncol1 - 2)) && (k < m - 1))
                                                    {
                                                        objs.Add(value2.ToString());
                                                        k++;
                                                    }

                                                }
                                                if ((k == m - 1) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) >= Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                {

                                                    objs.Add(tpl1.ValuesOnPerRow[ncol1 - 1]);
                                                }
                                                else
                                                {
                                                    if ((k == m - 1) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) < Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                    {
                                                        objs.Add(tpl2.ValuesOnPerRow[ncol2 - 1]);
                                                    }

                                                }
                                                FzTupleEntity tplab = new FzTupleEntity() { ValuesOnPerRow = objs };
                                                rlAB.Tuples.Add(tplab);
                                                row++;

                                            }
                                        }
                                        if(valuecheck == false)
                                        {
                                                List<Object> objs = new List<object>();
                                                int k = 0;
                                                int stt_cell;
                                                stt_cell = 0;
                                                foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                {
                                                    stt_cell++;

                                                    if ((k < ncol1 - 2) && (arr1[stt_cell - 1] == 0))
                                                    {
                                                        objs.Add(value1.ToString());
                                                        k++;
                                                    }

                                                }
                                                for(int a = 0; a < ncol2;a++)
                                                {
                                                    if ((k >= (ncol1 - 2)) && (k < m - 1))
                                                    {
                                                        objs.Add("NULL");
                                                        k++;
                                                    }
                                                    if (k == m - 1)
                                                    {

                                                        objs.Add(tpl1.ValuesOnPerRow[ncol1 - 1]);
                                                        k++;
                                                    }

                                                }
                                                FzTupleEntity tplab = new FzTupleEntity() { ValuesOnPerRow = objs };
                                                rlAB.Tuples.Add(tplab);
                                                row++;
                                        }
                                    }

                                    String queryAB = GetQueryAB(query) + " from " + rlAB.RelationName;
                                    QueryPL.StandardizeQuery(queryAB);
                                    QueryExcutetionBLL excutetionAB = new QueryExcutetionBLL(queryAB.ToLower(), newFdb.Relations);
                                    FzRelationEntity resultAB = new FzRelationEntity();
                                    this._selectedAttributeTextsAB = GetAttributeTextsAB(query);
                                    this._conditionTextAB = GetConditionText(query);
                                    if (_conditionTextAB != String.Empty)
                                        this._conditionTextAB = AddParenthesis(this._conditionTextAB);
                                    this.GetSelectedAttr();
                                    if (this._error) throw new Exception(this._errorMessage);

                                    _errorMessage = ExistsAttribute();
                                    if (ErrorMessage != "") { this.Error = true; throw new Exception(_errorMessage); }
                                    if (query.Contains("where"))
                                    {
                                        List<Item> items = FormatCondition(this._conditionTextAB);
                                        //Check fuzzy set and object here
                                        this.ErrorMessage = ExistsFuzzySet(items);
                                        if (ErrorMessage != "")
                                        {

                                            ShowMessage(ErrorMessage, Color.Red); return;
                                        }

                                        QueryConditionBLL1 condition = new QueryConditionBLL1(items, this.rlAB);
                                        resultAB.Scheme.Attributes = this._selectedAttributesAB;

                                        foreach (FzTupleEntity tuple in this.rlAB.Tuples)
                                        {
                                            if (condition.Satisfy(items, tuple))
                                            {
                                                if (this._selectedAttributeTextsAB != null)
                                                    resultAB.Tuples.Add(GetSelectedAttributes(condition.ResultTuple));
                                                else
                                                    resultAB.Tuples.Add(condition.ResultTuple);
                                            }
                                        }
                                    }
                                    else// Select all tuples
                                    {
                                        resultAB.Scheme.Attributes = this._selectedAttributesAB;
                                        resultAB.RelationName = this.rlAB.RelationName;

                                        if (this._selectedAttributeTextsAB != null)
                                        {
                                            foreach (var item in this.rlAB.Tuples)
                                                resultAB.Tuples.Add(GetSelectedAttributes(item));
                                        }
                                        else
                                        {
                                            foreach (var item in this.rlAB.Tuples)
                                                resultAB.Tuples.Add(item);
                                        }
                                    }

                                    if (resultAB != null)
                                    {
                                        foreach (FzAttributeEntity attribute in resultAB.Scheme.Attributes)
                                            GridViewResult.Columns.Add(attribute.AttributeName, attribute.AttributeName);

                                        int j, i = -1;
                                        foreach (FzTupleEntity tuple in resultAB.Tuples)
                                        {
                                            GridViewResult.Rows.Add();
                                            i++; j = -1;
                                            foreach (Object value in tuple.ValuesOnPerRow)
                                                GridViewResult.Rows[i].Cells[++j].Value = value.ToString();
                                        }

                                        xtraTabQueryResult.SelectedTabPageIndex = 0;
                                        //txtMessage.Text = "There are " + GridViewResult.RowCount + " row(s) affected";
                                    }
                                    else
                                    {
                                        txtMessage.Text = "There is no relation satisfy the condition";
                                        xtraTabQueryResult.SelectedTabPageIndex = 1;

                                    }
                                }
                            }
                            else
                            {
                                txtMessage.Text = "There is no relation satisfy the condition";
                                xtraTabQueryResult.SelectedTabPageIndex = 1;

                            }
                            siStatus.Caption = "Ready";
                            txtMessage.ForeColor = Color.Black;
                            txtMessage.Text = GridViewResult.RowCount + " row(s) affected";
                        }
                                        }
                                        else
                        if (query.Contains("right join"))
                        {
                            _errorMessage = null;
                            _error = false;
                            rlAB = new FzRelationEntity();
                            atAB = new List<FzAttributeEntity>();
                            _selectedAttributesAB = new List<FzAttributeEntity>();
                            _conditionTextAB = String.Empty;
                            _selectedAttributeTextsAB = null;
                            _indexAB = new List<int>();
                            String relationA = GetRelationTextsA(query);
                            String queryA = "select * from " + relationA;
                            QueryPL.StandardizeQuery(queryA);
                            String message = QueryPL.CheckSyntax(queryA);
                            if (message != "")
                            {
                                ShowMessage(message, Color.Red);
                                return;
                            }
                            QueryExcutetionBLL excutetionA = null;
                            excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);

                            String relationB = GetRelationB(query);
                            String queryB = "select * from " + relationB;
                            QueryPL.StandardizeQuery(queryB);
                            QueryExcutetionBLL excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                            FzRelationEntity resultA = null;
                            resultA = excutetionA.ExecuteQuery();
                            if (excutetionA.Error)
                            {
                                ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                            }
                            FzRelationEntity resultB = null;
                            resultB = excutetionB.ExecuteQuery();
                            if (excutetionB.Error)
                            {
                                ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                            }

                            if (resultA != null && resultB != null)
                            {
                                if (query.Contains("right join"))
                                {

                                    int ncol2 = resultA.Scheme.Attributes.Count;
                                    int nrow2 = resultA.Tuples.Count;
                                    int ncol1 = resultB.Scheme.Attributes.Count;
                                    int nrow1 = resultB.Tuples.Count;
                                    int m = 0;
                                    int[] arr1 = new int[ncol1];
                                    bool same;
                                    int stt = 0;
                                    int stt2;
                                    int dem = 0;
                                    int same1 = 0;
                                    int same2 = 0;
                                    foreach (FzAttributeEntity attribute1 in resultB.Scheme.Attributes)
                                    {

                                        same = false;
                                        stt++;
                                        stt2 = 0;
                                        foreach (FzAttributeEntity attribute2 in resultA.Scheme.Attributes)
                                        {
                                            stt2++;
                                            if ((attribute1.AttributeName.ToString() == attribute2.AttributeName.ToString()))
                                            {
                                                dem++;
                                                same = true;
                                                arr1[stt - 1] = 1;
                                                if (dem == 1)
                                                {
                                                    same1 = stt;
                                                    same2 = stt2;
                                                }
                                            }

                                        }
                                        if (same == false && (m < ncol1 - 2))
                                        {
                                            atAB.Add(attribute1);
                                            m++;
                                            arr1[stt - 1] = 0;
                                        }
                                        if (m == ncol1 - 2)
                                        {
                                            foreach (FzAttributeEntity attribute2 in resultA.Scheme.Attributes)
                                            {
                                                atAB.Add(attribute2);
                                                m++;
                                            }
                                        }
                                    }
                                    rlAB.Scheme.Attributes = atAB;

                                    int row = 0;
                                    if (dem != 2)
                                    {
                                        ShowMessage("Between two ralations, there is only one the same attribute", Color.Red);
                                        return;
                                    }
                                    else
                                    {

                                        FzTupleEntity tpl1;
                                        FzTupleEntity tpl2;
                                        bool valuecheck;
                                        for (int i = 0; i < nrow1; i++)
                                        {
                                            tpl1 = resultB.Tuples[i];
                                            valuecheck = false;
                                            for (int j = 0; j < nrow2; j++)
                                            {
                                                tpl2 = resultA.Tuples[j];
                                                if (tpl1.ValuesOnPerRow[same1 - 1].ToString() == tpl2.ValuesOnPerRow[same2 - 1].ToString())
                                                {
                                                    valuecheck = true;
                                                    List<Object> objs = new List<object>();
                                                    int k = 0;
                                                    int stt_cell;
                                                    stt_cell = 0;
                                                    foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                    {
                                                        stt_cell++;

                                                        if ((k < ncol1 - 2) && (arr1[stt_cell - 1] == 0))
                                                        {
                                                            objs.Add(value1.ToString());
                                                            k++;
                                                        }

                                                    }
                                                    foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                    {
                                                        if ((k >= (ncol1 - 2)) && (k < m - 1))
                                                        {
                                                            objs.Add(value2.ToString());
                                                            k++;
                                                        }

                                                    }
                                                    if ((k == m - 1) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) >= Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                    {

                                                        objs.Add(tpl1.ValuesOnPerRow[ncol1 - 1]);
                                                    }
                                                    else
                                                    {
                                                        if ((k == m - 1) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) < Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                        {
                                                            objs.Add(tpl2.ValuesOnPerRow[ncol2 - 1]);
                                                        }

                                                    }
                                                    FzTupleEntity tplab = new FzTupleEntity() { ValuesOnPerRow = objs };
                                                    rlAB.Tuples.Add(tplab);
                                                    row++;

                                                }
                                            }
                                            if (valuecheck == false)
                                            {
                                                List<Object> objs = new List<object>();
                                                int k = 0;
                                                int stt_cell;
                                                stt_cell = 0;
                                                foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                {
                                                    stt_cell++;

                                                    if ((k < ncol1 - 2) && (arr1[stt_cell - 1] == 0))
                                                    {
                                                        objs.Add(value1.ToString());
                                                        k++;
                                                    }

                                                }
                                                for (int a = 0; a < ncol2; a++)
                                                {
                                                    if ((k >= (ncol1 - 2)) && (k < m - 1))
                                                    {
                                                        objs.Add("NULL");
                                                        k++;
                                                    }
                                                    if ((k == m - 1))
                                                    {
                                                        objs.Add(tpl1.ValuesOnPerRow[ncol1 - 1]);
                                                        k++;
                                                    }

                                                }

                                                FzTupleEntity tplab = new FzTupleEntity() { ValuesOnPerRow = objs };
                                                rlAB.Tuples.Add(tplab);
                                                row++;
                                            }
                                        }

                                        String queryAB = GetQueryAB(query) + " from " + rlAB.RelationName;
                                        QueryPL.StandardizeQuery(queryAB);
                                        QueryExcutetionBLL excutetionAB = new QueryExcutetionBLL(queryAB.ToLower(), newFdb.Relations);
                                        FzRelationEntity resultAB = new FzRelationEntity();
                                        this._selectedAttributeTextsAB = GetAttributeTextsAB(query);
                                        this._conditionTextAB = GetConditionText(query);
                                        if (_conditionTextAB != String.Empty)
                                            this._conditionTextAB = AddParenthesis(this._conditionTextAB);
                                        this.GetSelectedAttr();
                                        if (this._error) throw new Exception(this._errorMessage);

                                        _errorMessage = ExistsAttribute();
                                        if (ErrorMessage != "") { this.Error = true; throw new Exception(_errorMessage); }
                                        if (query.Contains("where"))
                                        {
                                            List<Item> items = FormatCondition(this._conditionTextAB);
                                            //Check fuzzy set and object here
                                            this.ErrorMessage = ExistsFuzzySet(items);
                                            if (ErrorMessage != "")
                                            {

                                                ShowMessage(ErrorMessage, Color.Red); return;
                                            }

                                            QueryConditionBLL1 condition = new QueryConditionBLL1(items, this.rlAB);
                                            resultAB.Scheme.Attributes = this._selectedAttributesAB;

                                            foreach (FzTupleEntity tuple in this.rlAB.Tuples)
                                            {
                                                if (condition.Satisfy(items, tuple))
                                                {
                                                    if (this._selectedAttributeTextsAB != null)
                                                        resultAB.Tuples.Add(GetSelectedAttributes(condition.ResultTuple));
                                                    else
                                                        resultAB.Tuples.Add(condition.ResultTuple);
                                                }
                                            }
                                        }
                                        else// Select all tuples
                                        {
                                            resultAB.Scheme.Attributes = this._selectedAttributesAB;
                                            resultAB.RelationName = this.rlAB.RelationName;

                                            if (this._selectedAttributeTextsAB != null)
                                            {
                                                foreach (var item in this.rlAB.Tuples)
                                                    resultAB.Tuples.Add(GetSelectedAttributes(item));
                                            }
                                            else
                                            {
                                                foreach (var item in this.rlAB.Tuples)
                                                    resultAB.Tuples.Add(item);
                                            }
                                        }

                                        if (resultAB != null)
                                        {
                                            foreach (FzAttributeEntity attribute in resultAB.Scheme.Attributes)
                                                GridViewResult.Columns.Add(attribute.AttributeName, attribute.AttributeName);

                                            int j, i = -1;
                                            foreach (FzTupleEntity tuple in resultAB.Tuples)
                                            {
                                                GridViewResult.Rows.Add();
                                                i++; j = -1;
                                                foreach (Object value in tuple.ValuesOnPerRow)
                                                    GridViewResult.Rows[i].Cells[++j].Value = value.ToString();
                                            }

                                            xtraTabQueryResult.SelectedTabPageIndex = 0;
                                            //txtMessage.Text = "There are " + GridViewResult.RowCount + " row(s) affected";
                                        }
                                        else
                                        {
                                            txtMessage.Text = "There is no relation satisfy the condition";
                                            xtraTabQueryResult.SelectedTabPageIndex = 1;

                                        }

                                    }
                                }
                                else
                                {
                                    txtMessage.Text = "There is no relation satisfy the condition";
                                    xtraTabQueryResult.SelectedTabPageIndex = 1;

                                }
                                siStatus.Caption = "Ready";
                                txtMessage.ForeColor = Color.Black;
                                txtMessage.Text = GridViewResult.RowCount + " row(s) affected";
                            }
                                            }
                                            else
                                            {
                                                this._selectedRelationTextsAB = null;
                                        lrlAB = new List<FzRelationEntity>();
                                        this._selectedRelationTextsAB = GetRelationTexts(query);
                                        this.GetSectedRelation(newFdb.Relations);
                                        if (this._error) throw new Exception(this._errorMessage);

                                        int t= 0;
                                        t = lrlAB.Count;
                                        if (t >= 3)
                                        {
                                            ShowMessage("Don't support with three or more relations", Color.Red);
                                            return;
                                        }
                                        else
                                        {
                                            if (t == 2)
                                            {

                                                _errorMessage = null;
                                                _error = false;
                                                rlAB = new FzRelationEntity();
                                                atAB = new List<FzAttributeEntity>();
                                                _selectedAttributesAB = new List<FzAttributeEntity>();
                                                _conditionTextAB = String.Empty;
                                                _selectedAttributeTextsAB = null;
                                                _indexAB = new List<int>();

                                                String queryA = null;
                                                queryA = "select * from " + lrlAB[0].RelationName;
                                                QueryPL.StandardizeQuery(queryA);
                                                String messageA = null;
                                                messageA = QueryPL.CheckSyntax(queryA);
                                                if (messageA != "")
                                                {
                                                    ShowMessage(messageA, Color.Red);
                                                    return;
                                                }

                                                String queryB = "select * from " + lrlAB[1].RelationName;
                                                QueryPL.StandardizeQuery(queryB);
                                                String messageB = null;
                                                messageB = QueryPL.CheckSyntax(queryA);
                                                if (messageB != "")
                                                {
                                                    ShowMessage(messageB, Color.Red);
                                                    return;
                                                }
                                                QueryExcutetionBLL excutetionA = null;
                                                excutetionA = new QueryExcutetionBLL(queryA.ToLower(), newFdb.Relations);
                                                QueryExcutetionBLL excutetionB = null;
                                                excutetionB = new QueryExcutetionBLL(queryB.ToLower(), newFdb.Relations);
                                                FzRelationEntity resultA = null;
                                                resultA = excutetionA.ExecuteQuery();
                                                if (excutetionA.Error)
                                                {
                                                    ShowMessage(excutetionA.ErrorMessage, Color.Red); return;
                                                }
                                                FzRelationEntity resultB = null;
                                                resultB = excutetionB.ExecuteQuery();
                                                if (excutetionB.Error)
                                                {
                                                    ShowMessage(excutetionB.ErrorMessage, Color.Red); return;
                                                }
                                                if (resultA != null && resultB != null)
                                                {
                                                    int[] arrAB = new int[resultA.Scheme.Attributes.Count];
                                                    int same_att = 0;
                                                    int a = 0;
                                                    bool valueAB;
                                                    foreach (FzAttributeEntity att1 in resultA.Scheme.Attributes)
                                                    {
                                                        a++;
                                                        valueAB = false;
                                                        foreach (FzAttributeEntity att2 in resultB.Scheme.Attributes)
                                                        {
                                                            if ((att1.AttributeName.Equals(att2.AttributeName)) && (a < resultA.Scheme.Attributes.Count))
                                                            {
                                                                valueAB = true;
                                                                same_att++;

                                                            }

                                                        }
                                                        if (valueAB == true)
                                                        {
                                                            arrAB[a - 1] = 1;
                                                        }
                                                        else
                                                        {
                                                            arrAB[a - 1] = 0;
                                                        }
                                                    }
                                                    if (same_att == 0)
                                                    {
                                                        int ncol1 = resultA.Scheme.Attributes.Count;
                                                        int nrow1 = resultA.Tuples.Count;
                                                        int ncol2 = resultB.Scheme.Attributes.Count;
                                                        int nrow2 = resultB.Tuples.Count;
                                                        int m = 0;

                                                        FzTupleEntity tpl1;
                                                        FzTupleEntity tpl2;
                                                        foreach (FzAttributeEntity attribute2 in resultB.Scheme.Attributes)
                                                        {
                                                            if (m == 0)
                                                            {
                                                                foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                                                {

                                                                    if (m < ncol1 - 1)
                                                                    {
                                                                        atAB.Add(attribute1);
                                                                        m++;

                                                                    }
                                                                }
                                                            }

                                                            atAB.Add(attribute2);
                                                            m++;

                                                        }

                                                        rlAB.Scheme.Attributes = atAB;
                                                        int r = 0;

                                                        for (int i = 0; i < nrow1; i++)
                                                        {
                                                            tpl1 = resultA.Tuples[i];
                                                            for (int j = 0; j < nrow2; j++)
                                                            {
                                                                List<Object> objs = new List<object>();

                                                                tpl2 = resultB.Tuples[j];
                                                                int k = 0;
                                                                foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                                {

                                                                    if (k < ncol1 - 1)
                                                                    {
                                                                        objs.Add(value1.ToString());
                                                                        k++;

                                                                    }

                                                                }
                                                                foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                                {
                                                                    if ((k >= ncol1 - 1) && (k < m - 1))
                                                                    {
                                                                        objs.Add(value2.ToString());
                                                                        k++;
                                                                    }
                                                                    if (k == m - 1 && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) <= Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                                    {
                                                                        objs.Add(tpl1.ValuesOnPerRow[ncol1 - 1]);
                                                                        k++;
                                                                    }
                                                                    if (k == m - 1 && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) > Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                                    {
                                                                        objs.Add(tpl2.ValuesOnPerRow[ncol2 - 1]);
                                                                        k++;
                                                                    }
                                                                }

                                                                FzTupleEntity tplab = new FzTupleEntity() { ValuesOnPerRow = objs };
                                                                rlAB.Tuples.Add(tplab);
                                                                r++;

                                                            }

                                                        }
                                                        String queryAB = GetQueryAB(query) + " from " + rlAB.RelationName;
                                                        QueryPL.StandardizeQuery(queryAB);
                                                        QueryExcutetionBLL excutetionAB = new QueryExcutetionBLL(queryAB.ToLower(), newFdb.Relations);
                                                        FzRelationEntity resultAB = new FzRelationEntity();
                                                        this._selectedAttributeTextsAB = GetAttributeTextsAB(query);
                                                        this._conditionTextAB = GetConditionText(query);
                                                        if (_conditionTextAB != String.Empty)
                                                            this._conditionTextAB = AddParenthesis(this._conditionTextAB);
                                                        this.GetSelectedAttr();
                                                        if (this._error) throw new Exception(this._errorMessage);

                                                        _errorMessage = ExistsAttribute();
                                                        if (ErrorMessage != "") { this.Error = true; throw new Exception(_errorMessage); }
                                                        if (query.Contains("where"))
                                                        {
                                                            List<Item> items = FormatCondition(this._conditionTextAB);
                                                            //Check fuzzy set and object here
                                                            this.ErrorMessage = ExistsFuzzySet(items);
                                                            if (ErrorMessage != "")
                                                            {

                                                                ShowMessage(ErrorMessage, Color.Red); return;
                                                            }

                                                            QueryConditionBLL1 condition = new QueryConditionBLL1(items, this.rlAB);
                                                            resultAB.Scheme.Attributes = this._selectedAttributesAB;

                                                            foreach (FzTupleEntity tuple in this.rlAB.Tuples)
                                                            {
                                                                if (condition.Satisfy(items, tuple))
                                                                {
                                                                    if (this._selectedAttributeTextsAB != null)
                                                                        resultAB.Tuples.Add(GetSelectedAttributes(condition.ResultTuple));
                                                                    else
                                                                        resultAB.Tuples.Add(condition.ResultTuple);
                                                                }
                                                            }
                                                        }
                                                        else// Select all tuples
                                                        {
                                                            resultAB.Scheme.Attributes = this._selectedAttributesAB;
                                                            resultAB.RelationName = this.rlAB.RelationName;

                                                            if (this._selectedAttributeTextsAB != null)
                                                            {
                                                                foreach (var item in this.rlAB.Tuples)
                                                                    resultAB.Tuples.Add(GetSelectedAttributes(item));
                                                            }
                                                            else
                                                            {
                                                                foreach (var item in this.rlAB.Tuples)
                                                                    resultAB.Tuples.Add(item);
                                                            }
                                                        }

                                                        if (resultAB != null)
                                                        {
                                                            foreach (FzAttributeEntity attribute in resultAB.Scheme.Attributes)
                                                                GridViewResult.Columns.Add(attribute.AttributeName, attribute.AttributeName);

                                                            int j, i = -1;
                                                            foreach (FzTupleEntity tuple in resultAB.Tuples)
                                                            {
                                                                GridViewResult.Rows.Add();
                                                                i++; j = -1;
                                                                foreach (Object value in tuple.ValuesOnPerRow)
                                                                    GridViewResult.Rows[i].Cells[++j].Value = value.ToString();
                                                            }

                                                            xtraTabQueryResult.SelectedTabPageIndex = 0;
                                                        }
                                                        else
                                                        {
                                                            txtMessage.Text = "There is no relation satisfy the condition";
                                                            xtraTabQueryResult.SelectedTabPageIndex = 1;
                                                        }
                                                        siStatus.Caption = "Ready";
                                                        txtMessage.ForeColor = Color.Black;
                                                        txtMessage.Text = "This is decartes operation."+" There are " + GridViewResult.RowCount + " row(s) affected";

                                                    }
                                                    if (same_att == 1)
                                                    {
                                                        int ncol1 = resultA.Scheme.Attributes.Count;
                                                        int nrow1 = resultA.Tuples.Count;
                                                        int ncol2 = resultB.Scheme.Attributes.Count;
                                                        int nrow2 = resultB.Tuples.Count;
                                                        int m = 0;

                                                        bool same;
                                                        int stt = 0;
                                                        int sttvalue = 0;
                                                        int same1 = 0;
                                                        int same2 = 0;
                                                        int dem = 0;
                                                        int stt2;
                                                        int[] arrAB1 = new int[ncol1];
                                                        foreach (FzAttributeEntity attribute1 in resultA.Scheme.Attributes)
                                                        {

                                                            same = false;
                                                            stt++;
                                                            stt2 = 0;
                                                            foreach (FzAttributeEntity attribute2 in resultB.Scheme.Attributes)
                                                            {
                                                                stt2++;
                                                                if ((attribute1.AttributeName.ToString() == attribute2.AttributeName.ToString()))
                                                                {
                                                                    dem++;
                                                                    same = true;
                                                                    arrAB1[stt - 1] = 1;
                                                                    if (dem == 1)
                                                                    {
                                                                        same1 = stt;
                                                                        same2 = stt2;
                                                                    }
                                                                }

                                                            }
                                                            if (same == false && (m < ncol1 - 2))
                                                            {
                                                                atAB.Add(attribute1);
                                                                m++;
                                                                arrAB1[stt - 1] = 0;
                                                            }
                                                            if (m == ncol1 - 2)
                                                            {
                                                                foreach (FzAttributeEntity attribute2 in resultB.Scheme.Attributes)
                                                                {
                                                                    atAB.Add(attribute2);
                                                                    m++;
                                                                }
                                                            }
                                                        }
                                                        rlAB.Scheme.Attributes = atAB;
                                                        int row = 0;

                                                        FzTupleEntity tpl1;
                                                        FzTupleEntity tpl2;
                                                        for (int i = 0; i < nrow1; i++)
                                                        {

                                                            tpl1 = resultA.Tuples[i];
                                                            for (int j = 0; j < nrow2; j++)
                                                            {
                                                                tpl2 = resultB.Tuples[j];
                                                                if (tpl1.ValuesOnPerRow[same1 - 1].ToString() == tpl2.ValuesOnPerRow[same2 - 1].ToString())
                                                                {
                                                                    List<Object> objs = new List<object>();

                                                                    int k = 0;
                                                                    int stt_cell;
                                                                    stt_cell = 0;
                                                                    foreach (Object value1 in tpl1.ValuesOnPerRow)
                                                                    {
                                                                        stt_cell++;

                                                                        if ((k < ncol1 - 2) && (arrAB1[stt_cell - 1] == 0))
                                                                        {
                                                                            objs.Add(value1.ToString());
                                                                            k++;
                                                                        }

                                                                    }
                                                                    foreach (Object value2 in tpl2.ValuesOnPerRow)
                                                                    {
                                                                        if ((k >= (ncol1 - 2)) && (k < m - 1))
                                                                        {
                                                                            objs.Add(value2.ToString());
                                                                            k++;
                                                                        }

                                                                    }
                                                                    if ((k == m - 1) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) >= Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                                    {

                                                                        objs.Add(tpl1.ValuesOnPerRow[ncol1 - 1]);
                                                                    }
                                                                    else
                                                                    {
                                                                        if ((k == m - 1) && (Convert.ToDouble(tpl1.ValuesOnPerRow[ncol1 - 1]) < Convert.ToDouble(tpl2.ValuesOnPerRow[ncol2 - 1])))
                                                                        {
                                                                            objs.Add(tpl2.ValuesOnPerRow[ncol2 - 1]);
                                                                        }

                                                                    }
                                                                    FzTupleEntity tplab = new FzTupleEntity() { ValuesOnPerRow = objs };
                                                                    rlAB.Tuples.Add(tplab);
                                                                    row++;

                                                                }
                                                            }
                                                        }
                                                        String queryAB = GetQueryAB(query) + " from " + rlAB.RelationName;
                                                        QueryPL.StandardizeQuery(queryAB);
                                                        QueryExcutetionBLL excutetionAB = new QueryExcutetionBLL(queryAB.ToLower(), newFdb.Relations);
                                                        FzRelationEntity resultAB = new FzRelationEntity();
                                                        this._selectedAttributeTextsAB = GetAttributeTextsAB(query);
                                                        this._conditionTextAB = GetConditionText(query);
                                                        if (_conditionTextAB != String.Empty)
                                                            this._conditionTextAB = AddParenthesis(this._conditionTextAB);
                                                        this.GetSelectedAttr();
                                                        if (this._error) throw new Exception(this._errorMessage);

                                                        _errorMessage = ExistsAttribute();
                                                        if (ErrorMessage != "") { this.Error = true; throw new Exception(_errorMessage); }
                                                        if (query.Contains("where"))
                                                        {
                                                            List<Item> items = FormatCondition(this._conditionTextAB);
                                                            //Check fuzzy set and object here
                                                            this.ErrorMessage = ExistsFuzzySet(items);
                                                            if (ErrorMessage != "")
                                                            {

                                                                ShowMessage(ErrorMessage, Color.Red); return;
                                                            }

                                                            QueryConditionBLL1 condition = new QueryConditionBLL1(items, this.rlAB);
                                                            resultAB.Scheme.Attributes = this._selectedAttributesAB;

                                                            foreach (FzTupleEntity tuple in this.rlAB.Tuples)
                                                            {
                                                                if (condition.Satisfy(items, tuple))
                                                                {
                                                                    if (this._selectedAttributeTextsAB != null)
                                                                        resultAB.Tuples.Add(GetSelectedAttributes(condition.ResultTuple));
                                                                    else
                                                                        resultAB.Tuples.Add(condition.ResultTuple);
                                                                }
                                                            }
                                                        }
                                                        else// Select all tuples
                                                        {
                                                            resultAB.Scheme.Attributes = this._selectedAttributesAB;
                                                            resultAB.RelationName = this.rlAB.RelationName;

                                                            if (this._selectedAttributeTextsAB != null)
                                                            {
                                                                foreach (var item in this.rlAB.Tuples)
                                                                    resultAB.Tuples.Add(GetSelectedAttributes(item));
                                                            }
                                                            else
                                                            {
                                                                foreach (var item in this.rlAB.Tuples)
                                                                    resultAB.Tuples.Add(item);
                                                            }
                                                        }

                                                        if (resultAB != null)
                                                        {
                                                            foreach (FzAttributeEntity attribute in resultAB.Scheme.Attributes)
                                                                GridViewResult.Columns.Add(attribute.AttributeName, attribute.AttributeName);

                                                            int j, i = -1;
                                                            foreach (FzTupleEntity tuple in resultAB.Tuples)
                                                            {
                                                                GridViewResult.Rows.Add();
                                                                i++; j = -1;
                                                                foreach (Object value in tuple.ValuesOnPerRow)
                                                                    GridViewResult.Rows[i].Cells[++j].Value = value.ToString();
                                                            }

                                                            xtraTabQueryResult.SelectedTabPageIndex = 0;
                                                        }
                                                        else
                                                        {
                                                            txtMessage.Text = "There is no relation satisfy the condition";
                                                            xtraTabQueryResult.SelectedTabPageIndex = 1;
                                                        }
                                                        siStatus.Caption = "Ready";
                                                        txtMessage.ForeColor = Color.Black;
                                                        txtMessage.Text = "This is natural join operation." + " There are " + GridViewResult.RowCount + " row(s) affected";

                                                    }
                                                    else
                                                    {
                                                        txtMessage.Text = "Between two ralations, there is only one the same attribute";
                                                        xtraTabQueryResult.SelectedTabPageIndex = 1;
                                                    }
                                                }

                                            }

                                            else
                                            {
                                                String message = null;
                                                message = QueryPL.CheckSyntax(query);
                                                if (message != "")
                                                {
                                                    ShowMessage(message, Color.Red);
                                                    return;
                                                }
                                                QueryExcutetionBLL excutetion = null;
                                                excutetion = new QueryExcutetionBLL(query.ToLower(), newFdb.Relations);
                                                FzRelationEntity result = null;
                                                result = excutetion.ExecuteQuery();
                                                if (excutetion.Error)
                                                {
                                                    ShowMessage(excutetion.ErrorMessage, Color.Red); return;
                                                }

                                                if (query.Contains("oder by"))
                                                {
                                                    List<FzTupleEntity> listtuple = new List<FzTupleEntity>();
                                                    //List<FzAttributeEntity> listattr = new List<FzAttributeEntity>();
                                                    List<String> AttrList = new List<String>();

                                                    String[] condition, AttrSelect = null;

                                                    int i = 7;//Attribute after "select"
                                                    int j = query.IndexOf("from");
                                                    String tmp1 = query.Substring(i, j - i);
                                                    tmp1 = tmp1.Replace(" ", "");
                                                    AttrSelect = tmp1.Split(',');

                                                    int left = query.IndexOf("oder by") + 7;//Attribute after "oder by"
                                                    int right;
                                                    if (query.Contains("desc")){
                                                         right = query.IndexOf("desc");
                                                    }
                                                    else
                                                    {
                                                        if (query.Contains("asc")){
                                                            right = query.IndexOf("asc");
                                                        }
                                                        else { right = query.Length; }
                                                    }

                                                    String tmp = query.Substring(left, right - left);
                                                    tmp = tmp.Replace(" ", "");
                                                    condition = tmp.Split(',');

                                                    int indexofAttribute = 0;
                                                    for (int a = 0; a < condition.Length; a++ )
                                                    {
                                                        string temp = condition[a];
                                                        for (int b = 0; b < result.Scheme.Attributes.Count; b++)
                                                        {
                                                            if (result.Scheme.Attributes[b].AttributeName.ToString().ToLower().Contains(temp))
                                                            {
                                                                indexofAttribute = b;
                                                            }
                                                        }
                                                        for (int c = 0; c < result.Tuples.Count; c++)
                                                        {
                                                            AttrList.Add(result.Tuples[c].ValuesOnPerRow[indexofAttribute].ToString());
                                                        }
                                                    }
                                                    AttrList.Sort();
                                                    for (int d = 0; d < AttrList.Count - 1; d++)
                                                    {
                                                        if (AttrList[d] == AttrList[d + 1]) { AttrList.Remove(AttrList[d]); }
                                                    }

                                                    if (query.Contains("desc"))
                                                    {
                                                        for (int e = AttrList.Count - 1; e >= 0; e--)
                                                        {
                                                            string temp1 = AttrList[e];
                                                            for (int f = 0; f < result.Tuples.Count; f++)
                                                            {
                                                                if (AttrList[e].Equals(result.Tuples[f].ValuesOnPerRow[indexofAttribute]))
                                                                {
                                                                    listtuple.Add(result.Tuples[f]);
                                                                }
                                                            }
                                                        }
                                                    }
                                                    else
                                                    {
                                                        for (int e = 0; e < AttrList.Count; e++)
                                                        {
                                                            string temp = AttrList[e];
                                                            for (int f = 0; f < result.Tuples.Count; f++)
                                                            {
                                                                if (temp.Equals(result.Tuples[f].ValuesOnPerRow[indexofAttribute]))
                                                                {
                                                                    listtuple.Add(result.Tuples[f]);
                                                                }
                                                            }
                                                        }
                                                    }
                                                    result.Tuples.Clear();

                                                    foreach (FzTupleEntity tuple in listtuple)
                                                    {
                                                        result.Tuples.Add(tuple);
                                                    }

                                                }

                                                if(query.Contains("top")) {
                                                    int left = 11;//Attribute after "select"
                                                    int right = query.IndexOf("from");
                                                    String numtop = query.Substring(left, right - left - 1);
                                                    if (int.Parse(numtop.ToLower().ToString()) > result.Tuples.Count)
                                                    {
                                                        numtop = result.Tuples.Count.ToString();
                                                    }
                                                    List<FzTupleEntity> listtuple = new List<FzTupleEntity>();
                                                    for (int i = 0; i < int.Parse(numtop.ToLower().ToString()); i++) {
                                                        listtuple.Add(result.Tuples[i]);
                                                    }
                                                    result.Tuples.Clear();

                                                    foreach (FzTupleEntity tuple in listtuple) {
                                                        result.Tuples.Add(tuple);
                                                    }

                                                }

                                                if (query.Contains("max") || query.Contains("min") || query.Contains("sum") || query.Contains("avg"))
                                                {
                                                    int indexofAttr = 0;
                                                    int a = query.IndexOf("(");
                                                    int b = query.IndexOf(")");
                                                    string c = query.Substring(a, b - a);
                                                    c = c.Replace("(", "");
                                                    c = c.Replace(")", "");
                                                    c = c.Replace(" ", "");

                                                    int indexofAttrSum = 0;
                                                    int indexofAttrAvg = 0;
                                                    if (query.Contains("sum") || query.Contains("avg")) {
                                                         String[] AttrSumAvg = null;
                                                         int i = 7;//Attribute after "select"
                                                         int j = query.IndexOf("from");
                                                         String tmp1 = query.Substring(i, j - i);
                                                         tmp1 = tmp1.Replace(" ", "");
                                                         AttrSumAvg = tmp1.Split(',');
                                                         for (int ii = 0; ii < AttrSumAvg.Length; ii++)
                                                         {
                                                             if (AttrSumAvg[ii].Contains("sum")){
                                                                 indexofAttrSum = ii;
                                                                 if (AttrSumAvg[ii].Contains("max"))
                                                                 {
                                                                     c = c.Replace("max", "");
                                                                 }
                                                                 if (AttrSumAvg[ii].Contains("min"))
                                                                 {
                                                                     c = c.Replace("min", "");
                                                                 }
                                                             }
                                                             if (AttrSumAvg[ii].Contains("avg"))
                                                             {
                                                                 indexofAttrAvg = ii;
                                                             }
                                                         }
                                                    }

                                                    for (int j = 0; j < result.Scheme.Attributes.Count; j++)
                                                    {
                                                        if (result.Scheme.Attributes[j].AttributeName.ToString().ToLower().Contains(c))
                                                        {
                                                            indexofAttr = j;
                                                        }
                                                    }
                                                    double value = double.Parse(result.Tuples[0].ValuesOnPerRow[indexofAttr].ToString());
                                                    double membership = double.Parse(result.Tuples[0].ValuesOnPerRow[result.Scheme.Attributes.Count - 1].ToString());

                                                    double temp ;
                                                    for (int i = 1; i < result.Tuples.Count; i++)
                                                    {
                                                        temp = double.Parse(result.Tuples[i].ValuesOnPerRow[indexofAttr].ToString());
                                                        if (query.Contains("max"))
                                                        {
                                                            if (temp > value)
                                                            {
                                                                value = temp;
                                                            }
                                                        }

                                                        if (query.Contains("min"))
                                                        {
                                                            if (temp < value)
                                                            {
                                                                value = temp;
                                                            }
                                                        }
                                                        if (query.Contains("sum") || query.Contains("avg"))
                                                        {
                                                            if (query.Contains("max") || query.Contains("min"))
                                                            {
                                                                //value += temp;
                                                            }
                                                            else
                                                            {
                                                                value += temp;
                                                            }
                                                            if (membership > double.Parse(result.Tuples[i].ValuesOnPerRow[result.Scheme.Attributes.Count - 1].ToString()))
                                                            {
                                                                membership = double.Parse(result.Tuples[i].ValuesOnPerRow[result.Scheme.Attributes.Count - 1].ToString());
                                                            }
                                                        }
                                                    }

                                                    List<FzTupleEntity> listtuple = new List<FzTupleEntity>();

                                                    if (query.Contains("max") || query.Contains("min"))
                                                    {
                                                        for (int i = 0; i < result.Tuples.Count; i++)
                                                        {
                                                            if (double.Parse(result.Tuples[i].ValuesOnPerRow[indexofAttr].ToString()) == value)
                                                            {
                                                                listtuple.Add(result.Tuples[i]);
                                                            }
                                                        }
                                                    }
                                                    if (query.Contains("sum") || query.Contains("avg"))
                                                    {
                                                        if (query.Contains("sum"))
                                                        {
                                                            if (query.Contains("max") || query.Contains("min"))
                                                            {
                                                                result.Tuples[0].ValuesOnPerRow[indexofAttrSum] = value * listtuple.Count;
                                                            }
                                                            else
                                                            {
                                                                result.Tuples[0].ValuesOnPerRow[indexofAttrSum] = value;
                                                            }

                                                        }
                                                        if (query.Contains("avg"))
                                                        {
                                                            if (query.Contains("max") || query.Contains("min"))
                                                            {
                                                                result.Tuples[0].ValuesOnPerRow[indexofAttrAvg] = value;
                                                            }
                                                            else
                                                            {
                                                                result.Tuples[0].ValuesOnPerRow[indexofAttrAvg] = value / result.Tuples.Count;
                                                            }
                                                        }
                                                        result.Tuples[0].ValuesOnPerRow[result.Scheme.Attributes.Count - 1] = membership;
                                                        listtuple.Clear();
                                                        listtuple.Add(result.Tuples[0]);
                                                        //return;
                                                    }
                                                    result.Tuples.Clear();
                                                    foreach (FzTupleEntity tuple in listtuple)
                                                    {
                                                        result.Tuples.Add(tuple);
                                                    }

                                                }

                                                if (result != null)
                                                {
                                                    foreach (FzAttributeEntity attribute in result.Scheme.Attributes)
                                                        GridViewResult.Columns.Add(attribute.AttributeName, attribute.AttributeName);

                                                    int j, i = -1;
                                                    foreach (FzTupleEntity tuple in result.Tuples)
                                                    {
                                                        GridViewResult.Rows.Add();
                                                        i++; j = -1;
                                                        foreach (Object value in tuple.ValuesOnPerRow)
                                                            GridViewResult.Rows[i].Cells[++j].Value = value.ToString();
                                                    }

                                                    xtraTabQueryResult.SelectedTabPageIndex = 0;
                                                }
                                                else
                                                {
                                                    txtMessage.Text = "There are no relation satisfy the condition";
                                                    xtraTabQueryResult.SelectedTabPageIndex = 1;
                                                }

                                                siStatus.Caption = "Ready";
                                                txtMessage.ForeColor = Color.Black;
                                                txtMessage.Text = "There are " + GridViewResult.RowCount + " row(s) affected";

                                            }
                                        }

                                       }
                                    }
                                }
                            }

                        }
                    }
                }

            }
            catch (Exception ex)
            {
                return;
                //MessageBox.Show("ERROR:\n" + ex.Message);
            }
        }