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

在查询处理器使用的情况下, 如果true没有null聚合任何值, 则此属性为。Used by the query processor, this property is true if the aggregate returns null if no values have been accumulated.

错误设置此属性可能会导致不正确的查询结果。Incorrectly setting this property can result in incorrect query results. 此属性不是优化器提示;它会影响选定的计划和查询返回的结果。This property is not an optimizer hint; it affects the plan selected and the results returned by the query.

适用于