예제 #1
0
파일: Subquery.cs 프로젝트: deveel/deveeldb
        private static SqlQueryExpression Form(PlSqlParser.QueryBlockContext context, out IntoClause into)
        {
            var fromClause = FromClauseBuilder.Build(context.fromClause());

            SelectColumn[] columns;

            if (context.all != null) {
                columns = new[] {new SelectColumn(SqlExpression.Reference(new ObjectName("*")))};
            } else {
                columns = context.selectedElement().Select(SelectElement.BuildColumn).ToArray();
            }

            var query = new SqlQueryExpression(columns);

            into = null;

            if (context.DISTINCT() != null ||
                context.UNIQUE() != null)
                query.Distinct = true;

            var intoClause = context.into_clause();
            if (intoClause != null) {
                into = new IntoClause();

                if (intoClause.objectName() != null) {
                    into.TableName = Name.Object(intoClause.objectName());
                } else if (intoClause.variable_name() != null) {
                    into.Variables = intoClause.variable_name().Select(Name.Variable).ToArray();
                }
            }

            if (fromClause != null)
                query.FromClause = fromClause;

            var groupBy = context.groupByClause();
            if (groupBy != null && !groupBy.IsEmpty) {
                query.GroupBy = groupBy.groupByElements().expression().Select(x => new SqlExpressionVisitor().Visit(x));

                var having = groupBy.havingClause();
                if (having != null)
                    query.HavingExpression = new SqlExpressionVisitor().Visit(having.condition());
            }

            var groupMax = context.groupMaxClause();
            if (groupMax != null && !groupMax.IsEmpty) {
                var maxColumn = Name.Object(groupMax.objectName());
                query.GroupMax = maxColumn;
            }

            var whereClause = context.whereClause();
            if (whereClause != null && !whereClause.IsEmpty) {
                var currentOf = whereClause.current_of_clause();
                if (currentOf != null && !currentOf.IsEmpty) {
                    var cursorName = Name.Simple(currentOf.cursor_name());
                    throw new NotImplementedException();
                } else {
                    query.WhereExpression = new SqlExpressionVisitor().Visit(whereClause.conditionWrapper());
                }
            }

            return query;
        }