SqlUserDefinedAggregateAttribute.IsNullIfEmpty SqlUserDefinedAggregateAttribute.IsNullIfEmpty SqlUserDefinedAggregateAttribute.IsNullIfEmpty SqlUserDefinedAggregateAttribute.IsNullIfEmpty Property

定义

指示在没有对任何值进行累积时聚合是否返回 nullIndicates whether the aggregate returns null if no values have been accumulated.

public:
 property bool IsNullIfEmpty { bool get(); void set(bool value); };
public bool IsNullIfEmpty { get; set; }
member this.IsNullIfEmpty : bool with get, set
Public Property IsNullIfEmpty As Boolean

属性值

如果在没有对任何值进行累积时聚合返回 true,则为 null;否则为 falsetrue if the aggregate returns null if no values have been accumulated; otherwise false.

注解

由查询处理器,此属性是true如果聚合返回null如果任何值进行不累积。Used by the query processor, this property is true if the aggregate returns null if no values have been accumulated.

未正确设置此属性可能导致不正确的查询结果。Incorrectly setting this property can result in incorrect query results. 此属性不是一个优化程序提示;它会影响选择的计划和由查询返回的结果。This property is not an optimizer hint; it affects the plan selected and the results returned by the query.

适用于