Linq为什么忽略我的where子句?

Jus*_*ams 5 c# sql linq generated-sql azure-sql-database

我已经看到了几个StackOverflow问题,但它们似乎与我的情况不符.我保证我看了.

我对我的数据库有一些查询,我正在使用linq来做,我无法弄清楚为什么生成错误的SQL.这在我的代码中的几个地方发生.我希望我们只是陷入一些众所周知的陷阱,但我无法理解为什么Linq似乎决定我的where子句是愚蠢的,不应该将它添加到生成的SQL查询中.

为什么是这样?

例:

var testing = (from i in context.TableName1 where i.Param1 == object1.GuidParam select i).ToList();
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以上查询返回以下SQL

{SELECT 
    [Extent1].[RecordId] AS [RecordId], 
    [Extent1].[AnotherId] AS [AnotherId], 
    [Extent1].[YetAnotherId] AS [YetAnotherId], 
    [Extent1].[WeLikeIds] AS [WeLikeIds], 
    [Extent1].[WeReallyLikeIds] AS [WeReallyLikeIds]
    FROM [dbo].[SomeTable] AS [Extent1]}
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但是以下查询:

var testing = (from i in context.TableName1 where i.Param1 == object1.GuidParam select i);
var testingToList = testing.ToList();
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生成以下正确的SQL

{SELECT 
    [Extent1].[RecordId] AS [RecordId], 
    [Extent1].[AnotherId] AS [AnotherId], 
    [Extent1].[YetAnotherId] AS [YetAnotherId], 
    [Extent1].[WeLikeIds] AS [WeLikeIds], 
    [Extent1].[WeReallyLikeIds] AS [WeReallyLikeIds]
    FROM [dbo].[SomeTable] AS [Extent1]
WHERE [Extent1].[RecordId] = '78e49f5c-0ff8-e311-93f4-00155d514a6d'}
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mgr*_*ier -3

我更喜欢 lambda 表示法,但我不明白为什么这不起作用......

var testing = context.TableName1.Where(i => i.Param1 == object1.GuidParam).ToList();
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更干净、简洁,应该可以工作。