我正在尝试对这样的常量进行左连接:
SELECT
[t0].[DeviceId],
[t0].[DeviceTypeId],
[t0].[UnitId],
[t0].[UnitNum],
[t0].[ManPhone],
[t0].[Status],
[t2].[MaintDate] AS [ServiceExpiration]
FROM [dbo].[Devices] AS [t0]
INNER JOIN [dbo].[CustomerDevices] AS [t1]
ON ([t0].[DeviceId]) = [t1].[DeviceId]
LEFT JOIN [dbo].[Maintenance] AS [t2]
ON ([t0].[DeviceId]) = [t2].[DeviceId]
AND 8 = [t2].ActionId
我得到一个 CS1941当我像这样在 LINQ 中尝试它时:
var devices = from d in db.Devices
join cd in db.CustomerDevices
on d.DeviceId equals cd.DeviceId
join serviceExpiration in db.Maintenances
on
new { d.DeviceId, ActionId = 8 } // CS1941
equals
new { serviceExpiration.DeviceId, ActionId = serviceExpiration.ActionId } into j1
from deviceServiceExpiration in j1.DefaultIfEmpty()
最佳答案
从维护中尝试 ActionId == 8
首先,然后用这个加入反对。
var expirations = from serviceExpiration in db.Maintenances
where serviceExpiration.ActionId == 8
select serviceExpiration;
var devices = from d in db.Devices
join cd in db.CustomerDevices
on d.DeviceId equals cd.DeviceId
join e in expirations
on d.DeviceId = e.DeviceId into j1
from deviceServiceExpiration in j1.DefaultIfEmpty()
select deviceServiceExpiration;
关于linq - 如何在 LINQ 中加入常量?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/1862330/