出于EF linq查询的目的,First(c => cond)等于Where(c => cond).First()?

Aar*_*ide 3 c# linq-to-entities entity-framework-4

是否有任何隐藏的微妙,是一个被推崇,还是只是一个更短的方式来写另一个?

Client = db.Clients.First(c=>c.Name == "Client 1")
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Client = db.Clients.Where(c=>c.Name == "Client 1").First()
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Jet*_*hro 5

是的他们是等同的.

简单测试将它们添加到LINQPad并查看生成的SQL语句,并在我的数据库,会产生完全相同的查询.

更新:

下面是我对我的数据库的查询示例.

-- Region Parameters
DECLARE @p0 VarChar(1000) = 'SKY02'
-- EndRegion
SELECT TOP (1) [t0].[MST_SQ], [t0].[EMP_EMPNO]
FROM [EMPLOYEE] AS [t0]
WHERE [t0].[EMP_EMPNO] = @p0
GO

-- Region Parameters
DECLARE @p0 VarChar(1000) = 'SKY02'
-- EndRegion
SELECT TOP (1) [t0].[MST_SQ], [t0].[EMP_EMPNO]
FROM [EMPLOYEE] AS [t0]
WHERE [t0].[EMP_EMPNO] = @p0
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