Inheritance: Shaolinq.Persistence.Linq.Expressions.SqlExpressionVisitor
コード例 #1
0
        public static List <Tuple <string, Type> > Collect(Expression expression)
        {
            var collector = new SqlAliasTypeCollector();

            collector.Visit(expression);

            return(collector.results.ToList());
        }
コード例 #2
0
		public static List<Tuple<string, Type>> Collect(Expression expression)
		{
			var collector = new SqlAliasTypeCollector();
			
			collector.Visit(expression);

			return collector.results.ToList();
		}
コード例 #3
0
        protected override Expression VisitSelect(SqlSelectExpression selectExpression)
        {
            if (this.currentProjection == null || this.currentProjection.Select != selectExpression)
            {
                return(base.VisitSelect(selectExpression));
            }

            var objectType = selectExpression.Type.GetSequenceElementType();

            if (!objectType.IsDataAccessObjectType())
            {
                return(base.VisitSelect(selectExpression));
            }

            var aliasesAndTypes = SqlAliasTypeCollector.Collect(selectExpression)
                                  .ToDictionary(c => c.Item1, c => typeDescriptorProvider.GetTypeDescriptor(c.Item2.GetSequenceElementType() ?? c.Item2));

            List <SqlOrderByExpression> orderBys = null;
            var includeJoins = selectExpression.From.GetIncludeJoins().ToList();
            List <SqlColumnExpression> leftMostColumns = null;

            foreach (var includeJoin in includeJoins)
            {
                var equalsExpression = (BinaryExpression)SqlExpressionFinder.FindFirst(includeJoin, c => c.NodeType == ExpressionType.Equal);

                var left  = (SqlColumnExpression)equalsExpression.Left;
                var right = (SqlColumnExpression)equalsExpression.Right;

                var leftType  = aliasesAndTypes[left.SelectAlias];
                var rightType = aliasesAndTypes[right.SelectAlias];

                if (leftMostColumns == null)
                {
                    var typeDescriptor    = this.typeDescriptorProvider.GetTypeDescriptor(objectType);
                    var primaryKeyColumns = new HashSet <string>(QueryBinder.GetPrimaryKeyColumnInfos(this.typeDescriptorProvider, typeDescriptor).Select(c => c.ColumnName));

                    leftMostColumns = primaryKeyColumns
                                      .Select(c => new SqlColumnExpression(objectType, left.SelectAlias, c))
                                      .ToList();
                }

                var rightProperty = rightType.GetPropertyDescriptorByColumnName(right.Name);
                var leftProperty  = rightProperty.RelationshipInfo?.TargetProperty ?? leftType.GetPropertyDescriptorByColumnName(left.Name);

                if (leftProperty.PropertyType.GetGenericTypeDefinitionOrNull() == typeof(RelatedDataAccessObjects <>))
                {
                    var rightColumns = SqlExpressionFinder.FindAll(includeJoin, c => c.NodeType == (ExpressionType)SqlExpressionType.Column && ((SqlColumnExpression)c).SelectAlias == right.SelectAlias);
                    var leftColumns  = SqlExpressionFinder.FindAll(includeJoin, c => c.NodeType == (ExpressionType)SqlExpressionType.Column && ((SqlColumnExpression)c).SelectAlias == left.SelectAlias);

                    if (orderBys == null)
                    {
                        orderBys = new List <SqlOrderByExpression>();

                        if (selectExpression.OrderBy?.Count > 0)
                        {
                            orderBys.AddRange(selectExpression.OrderBy);
                            orderBys.AddRange(leftMostColumns.Select(c => new SqlOrderByExpression(OrderType.Ascending, c)));
                        }
                    }

                    orderBys.AddRange(rightColumns.Select(c => new SqlOrderByExpression(OrderType.Ascending, c)));
                    orderBys.AddRange(leftColumns.Select(c => new SqlOrderByExpression(OrderType.Ascending, c)));
                }
            }

            return(selectExpression.ChangeOrderBy(orderBys?.Distinct(SqlExpressionEqualityComparer <SqlOrderByExpression> .Default) ?? selectExpression.OrderBy));
        }