C# 具有内部select的LINQ Having子句
如何将以下内容转换为C# 具有内部select的LINQ Having子句,c#,linq-to-entities,C#,Linq To Entities,如何将以下内容转换为LINQ-EF select Name from TableA as TableAOuter group by TableAOuter.Name, TableAOuter.Id having( select count(TableAInner.Id) from TableA as TableAInner where TAbleAInner.Reference=TableAOuter.Id) = 0 ); 对我来说,这看起来像: var query =
LINQ
-EF
select Name
from TableA as TableAOuter
group by TableAOuter.Name, TableAOuter.Id
having(
select count(TableAInner.Id)
from TableA as TableAInner
where TAbleAInner.Reference=TableAOuter.Id) = 0
);
对我来说,这看起来像:
var query = from row in tableOuter
group row by new { row.Name, row.Id } into g
where !tableInner.Any(inner => inner.Reference == g.Key.Id)
select g.Key.Name;
虽然我很想在分组之前执行过滤,但此时您可以只对行名称进行分组:
var query = from row in tableOuter
where !tableInner.Any(row => inner.Reference == row.Id)
group row.Name by new { row.Name, row.Id };
我认为这应该做同样的事情,对吗?应该是
!tableInner.Any(inner=>inner.Reference==row.Id)
和grouprow.Name by new
?哎哟-我在这两种情况下都是指“grouprow by”。在第一个版本中,不能在where子句中使用row.Id
,因为它不在范围内。修正了这两个问题,简化了后一种方法。