Linq to SQL 在一个连接上具有更多条件

发布于 2024-12-10 15:32:11 字数 564 浏览 0 评论 0原文

我是 Linq to SQL 的新手，我正在尝试将此 SQL 转换为 Linq。你能帮我一下吗？

SELECT *
FROM [dbo].[tblTest]
INNER JOIN [dbo].[tblStationTest] ON [tblTest].[id] = [tblStationTest].[Test_id]
INNER JOIN [dbo].[tblTestType] ON [tblTest].[TestType_id] = [tblTestType].[id]
LEFT OUTER JOIN [dbo].[tblTestOrder] ON [tblTest].[id] = [tblTestOrder].[Test_id] 
              AND ([tblTestOrder].[TestOrderList_id] = 1)
WHERE ([Station_id] = 1)

导致我出现问题的是这个条件AND ([TestOrderList_id] = 1)

这个条件不能出现在Where类中，因为它会取消Left Join的效果

谢谢kurin

原文

I'm new to Linq to SQL and I'm trying to transform this SQL into Linq. Could you please help me out.

SELECT *
FROM [dbo].[tblTest]
INNER JOIN [dbo].[tblStationTest] ON [tblTest].[id] = [tblStationTest].[Test_id]
INNER JOIN [dbo].[tblTestType] ON [tblTest].[TestType_id] = [tblTestType].[id]
LEFT OUTER JOIN [dbo].[tblTestOrder] ON [tblTest].[id] = [tblTestOrder].[Test_id] 
              AND ([tblTestOrder].[TestOrderList_id] = 1)
WHERE ([Station_id] = 1)

What is causing me problem is this condition AND ([TestOrderList_id] = 1)

This condition can't be in Where clase because it will cancel the effect of Left Join

Thanks kurin

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

油饼 2024-12-17 15:32:11

你可以尝试类似的东西

from test in db.tblTest
    join stationTest in db.tblStationTest on test.id equals stationTest.Test_id
    join testType in db.tblTestType on test.TestType_id equals testType.id
    join testOrder in db.tblTestOrder on new{Key1  = test.id, Key2= 1} equals new{Key1 = testOrder.Test_id, Key2 = testOrder.TestOrderList_id} into tempOrders
   from t in tempOrders.DefaultIfEmpty()
   select new{test.Test_id, testType.something, t.somethingelse}

you can try something like

from test in db.tblTest
    join stationTest in db.tblStationTest on test.id equals stationTest.Test_id
    join testType in db.tblTestType on test.TestType_id equals testType.id
    join testOrder in db.tblTestOrder on new{Key1  = test.id, Key2= 1} equals new{Key1 = testOrder.Test_id, Key2 = testOrder.TestOrderList_id} into tempOrders
   from t in tempOrders.DefaultIfEmpty()
   select new{test.Test_id, testType.something, t.somethingelse}

回复收藏 0 原文

~没有更多了~