Beispiel #1
0
        public void WriteSql(SqlWriter writer, SqlGenerator sqlGenerator)
        {
            #region Check if FROM aliases need to be renamed

            // Create a list of the aliases used by the outer extents
            // JoinSymbols have to be treated specially.
            List <string> outerExtentAliases = null;
            if ((null != outerExtents) &&
                (0 < outerExtents.Count))
            {
                foreach (var outerExtent in outerExtents.Keys)
                {
                    var joinSymbol = outerExtent as JoinSymbol;
                    if (joinSymbol != null)
                    {
                        foreach (var symbol in joinSymbol.FlattenedExtentList)
                        {
                            if (null == outerExtentAliases)
                            {
                                outerExtentAliases = new List <string>();
                            }
                            outerExtentAliases.Add(symbol.NewName);
                        }
                    }
                    else
                    {
                        if (null == outerExtentAliases)
                        {
                            outerExtentAliases = new List <string>();
                        }
                        outerExtentAliases.Add(outerExtent.NewName);
                    }
                }
            }

            // An then rename each of the FromExtents we have
            // If AllJoinExtents is non-null - it has precedence.
            // The new name is derived from the old name - we append an increasing int.
            var extentList = AllJoinExtents ?? fromExtents;
            if (null != extentList)
            {
                foreach (var fromAlias in extentList)
                {
                    if ((null != outerExtentAliases) &&
                        outerExtentAliases.Contains(fromAlias.Name))
                    {
                        var    i = sqlGenerator.AllExtentNames[fromAlias.Name];
                        string newName;
                        do
                        {
                            ++i;
                            newName = fromAlias.Name + i.ToString(CultureInfo.InvariantCulture);
                        }while (sqlGenerator.AllExtentNames.ContainsKey(newName));
                        sqlGenerator.AllExtentNames[fromAlias.Name] = i;
                        fromAlias.NewName = newName;

                        // Add extent to list of known names (although i is always incrementing, "prefix11" can
                        // eventually collide with "prefix1" when it is extended)
                        sqlGenerator.AllExtentNames[newName] = 0;
                    }

                    // Add the current alias to the list, so that the extents
                    // that follow do not collide with me.
                    if (null == outerExtentAliases)
                    {
                        outerExtentAliases = new List <string>();
                    }
                    outerExtentAliases.Add(fromAlias.NewName);
                }
            }

            #endregion

            // Increase the indent, so that the Sql statement is nested by one tab.
            writer.Indent += 1; // ++ can be confusing in this context

            writer.Write("SELECT ");
            if (IsDistinct)
            {
                writer.Write("DISTINCT ");
            }

            if (Top != null &&
                Skip == null)    // This is simple TOP case. There is no OFFSET.
            {
                Top.WriteSql(writer, sqlGenerator);
            }

            if ((null == @select) ||
                Select.IsEmpty)
            {
                Debug.Assert(false); // we have removed all possibilities of SELECT *.
                writer.Write("*");
            }
            else
            {
                Select.WriteSql(writer, sqlGenerator);
            }

            writer.WriteLine();
            writer.Write("FROM ");
            From.WriteSql(writer, sqlGenerator);

            if ((null != @where) &&
                !Where.IsEmpty)
            {
                writer.WriteLine();
                writer.Write("WHERE ");
                Where.WriteSql(writer, sqlGenerator);
            }

            if ((null != groupBy) &&
                !GroupBy.IsEmpty)
            {
                writer.WriteLine();
                writer.Write("GROUP BY ");
                GroupBy.WriteSql(writer, sqlGenerator);
            }

            if ((null != orderBy) &&
                !OrderBy.IsEmpty &&
                (IsTopMost || Top != null || Skip != null))
            {
                writer.WriteLine();
                writer.Write("ORDER BY ");
                OrderBy.WriteSql(writer, sqlGenerator);
            }

            if (null != Skip)
            {
                writer.WriteLine();
                WriteOffsetFetch(writer, Top, Skip, sqlGenerator); // Write OFFSET, FETCH clause.
            }

            --writer.Indent;
        }
        public void WriteSql(SqlWriter writer, SqlGenerator sqlGenerator)
        {
            #region Check if FROM aliases need to be renamed

            // Create a list of the aliases used by the outer extents
            // JoinSymbols have to be treated specially.
            List<string> outerExtentAliases = null;
            if ((null != outerExtents)
                && (0 < outerExtents.Count))
            {
                foreach (var outerExtent in outerExtents.Keys)
                {
                    var joinSymbol = outerExtent as JoinSymbol;
                    if (joinSymbol != null)
                    {
                        foreach (var symbol in joinSymbol.FlattenedExtentList)
                        {
                            if (null == outerExtentAliases)
                            {
                                outerExtentAliases = new List<string>();
                            }
                            outerExtentAliases.Add(symbol.NewName);
                        }
                    }
                    else
                    {
                        if (null == outerExtentAliases)
                        {
                            outerExtentAliases = new List<string>();
                        }
                        outerExtentAliases.Add(outerExtent.NewName);
                    }
                }
            }

            // An then rename each of the FromExtents we have
            // If AllJoinExtents is non-null - it has precedence.
            // The new name is derived from the old name - we append an increasing int.
            var extentList = AllJoinExtents ?? fromExtents;
            if (null != extentList)
            {
                foreach (var fromAlias in extentList)
                {
                    if ((null != outerExtentAliases)
                        && outerExtentAliases.Contains(fromAlias.Name))
                    {
                        var i = sqlGenerator.AllExtentNames[fromAlias.Name];
                        string newName;
                        do
                        {
                            ++i;
                            newName = fromAlias.Name + i.ToString(CultureInfo.InvariantCulture);
                        }
                        while (sqlGenerator.AllExtentNames.ContainsKey(newName));
                        sqlGenerator.AllExtentNames[fromAlias.Name] = i;
                        fromAlias.NewName = newName;

                        // Add extent to list of known names (although i is always incrementing, "prefix11" can
                        // eventually collide with "prefix1" when it is extended)
                        sqlGenerator.AllExtentNames[newName] = 0;
                    }

                    // Add the current alias to the list, so that the extents
                    // that follow do not collide with me.
                    if (null == outerExtentAliases)
                    {
                        outerExtentAliases = new List<string>();
                    }
                    outerExtentAliases.Add(fromAlias.NewName);
                }
            }

            #endregion

            // Increase the indent, so that the Sql statement is nested by one tab.
            writer.Indent += 1; // ++ can be confusing in this context

            writer.Write("SELECT ");
            if (IsDistinct)
            {
                writer.Write("DISTINCT ");
            }

            if (Top != null
                && Skip == null) // This is simple TOP case. There is no OFFSET.
            {
                Top.WriteSql(writer, sqlGenerator);
            }

            if ((null == @select)
                || Select.IsEmpty)
            {
                Debug.Assert(false); // we have removed all possibilities of SELECT *.
                writer.Write("*");
            }
            else
            {
                Select.WriteSql(writer, sqlGenerator);
            }

            writer.WriteLine();
            writer.Write("FROM ");
            From.WriteSql(writer, sqlGenerator);

            if ((null != @where)
                && !Where.IsEmpty)
            {
                writer.WriteLine();
                writer.Write("WHERE ");
                Where.WriteSql(writer, sqlGenerator);
            }

            if ((null != groupBy)
                && !GroupBy.IsEmpty)
            {
                writer.WriteLine();
                writer.Write("GROUP BY ");
                GroupBy.WriteSql(writer, sqlGenerator);
            }

            if ((null != orderBy)
                && !OrderBy.IsEmpty
                && (IsTopMost || Top != null || Skip != null))
            {
                writer.WriteLine();
                writer.Write("ORDER BY ");
                OrderBy.WriteSql(writer, sqlGenerator);
            }

            if (null != Skip)
            {
                writer.WriteLine();
                WriteOffsetFetch(writer, Top, Skip, sqlGenerator); // Write OFFSET, FETCH clause.
            }

            --writer.Indent;
        }