예제 #1
0
        private SqlFragment GenericFunction(Dictionary <string, string> funcs,
                                            DbFunctionExpression e)
        {
            SqlFragment[] frags = new SqlFragment[e.Arguments.Count];

            for (int i = 0; i < e.Arguments.Count; i++)
            {
                frags[i] = e.Arguments[i].Accept(callingGenerator);
            }

            string sql;

            switch (e.Function.Name)
            {
            case "Round":
                // Special handling for Round as it has more than one signature.
                sql = HandleFunctionRound(e);
                break;

            default:
                sql = String.Format(funcs[e.Function.Name], frags);
                break;
            }

            return(new LiteralFragment(sql));
        }
예제 #2
0
        private SqlFragment HandleFunction(DbFunctionAggregate fa, SqlFragment arg)
        {
            Debug.Assert(fa.Arguments.Count == 1);

            if (fa.Function.NamespaceName != "Edm")
            {
                throw new NotSupportedException();
            }

            FunctionFragment fragment = new FunctionFragment();

            fragment.Name = fa.Function.Name;
            if (fa.Function.Name == "BigCount")
            {
                fragment.Name = "COUNT";
            }
            else
            {
                fragment.Name = fa.Function.Name.ToUpperInvariant();
            }

            fragment.Distinct = fa.Distinct;
            fragment.Argument = arg;
            return(fragment);
            //return new CastExpression(aggregate, GetDbType(functionAggregate.ResultType.EdmType));
        }
예제 #3
0
 public void AddGroupBy(SqlFragment f)
 {
     if (GroupBy == null)
     {
         GroupBy = new List <SqlFragment>();
     }
     GroupBy.Add(f);
 }
예제 #4
0
        public override SqlFragment Visit(DbConstantExpression expression)
        {
            SqlFragment value = null;

            if (_onReturningSelect && values.TryGetValue(_columnsVisited.Peek(), out value))
            {
                if (value is LiteralFragment)
                {
                    MySqlParameter par = Parameters.Find(p => p.ParameterName == (value as LiteralFragment).Literal);
                    if (par != null)
                    {
                        return(new LiteralFragment(par.ParameterName));
                    }
                }
            }
            return(base.Visit(expression));
        }
예제 #5
0
        public override string GenerateSQL(DbCommandTree tree)
        {
            DbQueryCommandTree commandTree = tree as DbQueryCommandTree;

            SqlFragment fragment = null;

            DbExpression e = commandTree.Query;

            switch (commandTree.Query.ExpressionKind)
            {
            case DbExpressionKind.Project:
                fragment = e.Accept(this);
                Debug.Assert(fragment is SelectStatement);
                break;
            }
            // Apply post-optimizations here:
            fragment = TryFlatteningGroupBy(fragment);
            return(fragment.ToString());
        }
예제 #6
0
        public override string GenerateSQL(DbCommandTree tree)
        {
            DbInsertCommandTree commandTree = tree as DbInsertCommandTree;

            InsertStatement statement = new InsertStatement();

            DbExpressionBinding e = commandTree.Target;

            statement.Target = (InputFragment)e.Expression.Accept(this);

            scope.Add("target", statement.Target);

            foreach (DbSetClause setClause in commandTree.SetClauses)
            {
                statement.Sets.Add(setClause.Property.Accept(this));
            }

            if (values == null)
            {
                values = new Dictionary <EdmMember, SqlFragment>();
            }

            foreach (DbSetClause setClause in commandTree.SetClauses)
            {
                DbExpression value         = setClause.Value;
                SqlFragment  valueFragment = value.Accept(this);
                statement.Values.Add(valueFragment);

                if (value.ExpressionKind != DbExpressionKind.Null)
                {
                    EdmMember property = ((DbPropertyExpression)setClause.Property).Property;
                    values.Add(property, valueFragment);
                }
            }

            if (commandTree.Returning != null)
            {
                statement.ReturningSelect = GenerateReturningSql(commandTree, commandTree.Returning);
            }

            return(statement.ToString());
        }
예제 #7
0
        public override string GenerateSQL(DbCommandTree tree)
        {
            DbUpdateCommandTree commandTree = tree as DbUpdateCommandTree;

            UpdateStatement statement = new UpdateStatement();

            _onReturningSelect = false;
            statement.Target   = commandTree.Target.Expression.Accept(this);
            scope.Add("target", statement.Target as InputFragment);

            if (values == null)
            {
                values = new Dictionary <EdmMember, SqlFragment>();
            }

            foreach (DbSetClause setClause in commandTree.SetClauses)
            {
                statement.Properties.Add(setClause.Property.Accept(this));
                DbExpression value         = setClause.Value;
                SqlFragment  valueFragment = value.Accept(this);
                statement.Values.Add(valueFragment);

                if (value.ExpressionKind != DbExpressionKind.Null)
                {
                    EdmMember property = ((DbPropertyExpression)setClause.Property).Property;
                    values.Add(property, valueFragment);
                }
            }

            statement.Where = commandTree.Predicate.Accept(this);

            _onReturningSelect = true;
            if (commandTree.Returning != null)
            {
                statement.ReturningSelect = GenerateReturningSql(commandTree, commandTree.Returning);
            }

            return(statement.ToString());
        }
예제 #8
0
        /// <summary>
        /// If input sqlFragment is a group by structure, is flattened to remove some nested correlation queries.
        /// </summary>
        /// <param name="input"></param>
        /// <returns></returns>
        private SqlFragment TryFlatteningGroupBy(SqlFragment input)
        {
            SelectStatement select = null;
            SelectStatement tmpFrag = null, tmpFrag2 = null, tmpFrag3 = null;
            InputFragment   table = null;
            string          objName = null, colName = null, queryName = null;

            // First part assert is a kind-of structure we are looking for
            tmpFrag = input as SelectStatement;
            if (tmpFrag == null)
            {
                goto NoChanges;
            }
            tmpFrag = (tmpFrag).From as SelectStatement;
            if (tmpFrag == null)
            {
                goto NoChanges;
            }
            queryName = tmpFrag.Name;
            if (tmpFrag.Columns.Count < 2)
            {
                goto NoChanges;
            }
            if (!(tmpFrag.Columns[0] is ColumnFragment))
            {
                goto NoChanges;
            }
            colName  = objName = (tmpFrag.Columns[0] as ColumnFragment).ActualColumnName;
            tmpFrag2 = tmpFrag.From as SelectStatement;
            if (tmpFrag2 == null)
            {
                goto NoChanges;
            }
            if (tmpFrag2.Columns.Count < 1 || !(tmpFrag2.Columns[0] is ColumnFragment))
            {
                goto NoChanges;
            }
            if (string.CompareOrdinal(objName, tmpFrag2.Columns[0].ActualColumnName) != 0)
            {
                goto NoChanges;
            }
            if (tmpFrag.Columns[1].Literal == null)
            {
                goto NoChanges;
            }
            tmpFrag2 = tmpFrag.Columns[1].Literal as SelectStatement;
            if (tmpFrag2 == null)
            {
                goto NoChanges;
            }
            if ((tmpFrag2.Columns.Count != 1) || !(tmpFrag2.Columns[0].Literal != null))
            {
                goto NoChanges;
            }
            tmpFrag3 = tmpFrag2.From as SelectStatement;
            if (tmpFrag3 == null)
            {
                goto NoChanges;
            }
            table = tmpFrag3.From as InputFragment;
            if (table == null)
            {
                goto NoChanges;
            }
            FunctionFragment func = tmpFrag2.Columns[0].Literal as FunctionFragment;

            if (tmpFrag3.Columns.Count != 1 || !(tmpFrag3.Columns[0] is ColumnFragment))
            {
                goto NoChanges;
            }
            if (func == null)
            {
                goto NoChanges;
            }
            // Yes it is the kind-of type we like, then optimize it
            select     = new SelectStatement(this);
            table.Name = null;
            string        tableName = null;
            TableFragment t         = tmpFrag3.From as TableFragment;

            if (t == null)
            {
                tableName = tmpFrag3.Columns[0].TableName;
            }
            else
            {
                tableName = t.Table;
            }
            select.From = table;
            select.Columns.Add(new ColumnFragment(tableName, colName));
            select.Columns.Add(new ColumnFragment(tableName, "C0")
            {
                ColumnAlias = "C1",
                Literal     = new FunctionFragment()
                {
                    Argument = new ColumnFragment(tableName, tmpFrag3.Columns[0].ActualColumnName),
                    Distinct = tmpFrag3.IsDistinct,
                    Name     = func.Name
                }
            });
            select.Wrap(null);
            select.Name = queryName;
            select.AddGroupBy(select.Columns[0]);
            (input as SelectStatement).From = select;
NoChanges:
            return(input);
        }
예제 #9
0
 public SortFragment(SqlFragment column, bool ascending)
 {
     Column    = column;
     Ascending = ascending;
 }
예제 #10
0
 public void Append(SqlFragment s)
 {
     Fragments.Add(s);
 }
예제 #11
0
 public ExistsFragment(SqlFragment f)
 {
     Argument = f;
 }