使用Linq连接同一表中的多列

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我想将以下sql查询转换为Linq到sql

select distinct r.CompanyLogo, j.JobName, j.JobId, ur.UserId, r.JobSeekerID
, ur.FirstName, j.JobType, j.JobCareerLevel, j.JobLocation
from UserInterest m
join job j on m.FunctionalId = j.FunctionId or m.Careerlevel = j.CarrerLevelId or m.SalId = j.SalaryRangeId
join UserRegistration ur on j.UserId = ur.UserId
join EmplrRegistration r on j.UserId = r.JobSeekerID
where m.Status = 1 and m.UserId = 1

经历了这一切,到目前为止,我已经尝试了以下操作,但没有成功

var list = (from m in entities.UserInterests
from j in entities.Jobs
where m.FunctionalId == j.FunctionId || m.SalId == j.SalaryRangeId || m.Careerlevel == j.CarrerLevelId
&& m.Status == true && m.UserId == 1
join ur in entities.UserRegistrations on m.UserId equals ur.UserId
join r in entities.EmplrRegistrations on m.UserId equals r.JobSeekerID
select new { r.CompanyLogo, j.JobName, j.JobId, ur.UserId, r.JobSeekerID
, ur.FirstName, j.JobType, j.JobCareerLevel, j.JobLocation }).Distinct().ToList();

编辑:下面的查询是针对Svyatoslav Danyliv的答案生成的,该答案返回7行而不是6个

SELECT 1 AS [C1], [Extent4].[CompanyLogo] AS [CompanyLogo], [Extent2].[JobName] AS [JobName]
,[Extent2].[JobId] AS [JobId], [Extent3].[UserId] AS [UserId]
,[Extent4].[JobSeekerID] AS [JobSeekerID], [Extent3].[FirstName] AS [FirstName]
,[Extent2].[JobType] AS [JobType], [Extent2].[JobCareerLevel] AS [JobCareerLevel]
,[Extent2].[JobLocation] AS [JobLocation]
FROM [dbo].[UserInterest] AS [Extent1]
INNER JOIN [dbo].[Job] AS [Extent2] ON ([Extent1].[FunctionalId] = [Extent2].[FunctionId])
OR (([Extent1].[FunctionalId] IS NULL) AND ([Extent2].[FunctionId] IS NULL))
OR ([Extent1].[Careerlevel] = [Extent2].[CarrerLevelId])
OR (([Extent1].[Careerlevel] IS NULL) AND ([Extent2].[CarrerLevelId] IS NULL))
OR ([Extent1].[SalId] = [Extent2].[SalaryRangeId])
OR (([Extent1].[SalId] IS NULL)
AND ([Extent2].[SalaryRangeId] IS NULL))
INNER JOIN [dbo].[UserRegistration] AS [Extent3] ON [Extent2].[UserId] = [Extent3].[UserId]
INNER JOIN [dbo].[EmplrRegistration] AS [Extent4] ON [Extent2].[UserId] = [Extent4].[JobSeekerID]
WHERE (1 = [Extent1].[Status]) AND (1 = [Extent1].[UserId])

通过from x in entities.Where(x => ..)可以实现不仅包含AND表达式的Join。你已经做了部分,并在哪里的条件下犯了错误。

更正了查询,看起来与原始SQL 相同

var query = 
from m in entities.UserInterests
from j in entities.Jobs.Where(j => 
m.FunctionalId != null && m.FunctionalId == j.FunctionId || 
m.Careerlevel != null && m.Careerlevel == j.CarrerLevelId || 
m.SalId != null && m.SalId == j.SalaryRangeId)
join ur in entities.UserRegistrations on j.UserId equals ur.UserId
join r in entities.EmplrRegistrations on j.UserId equals r.JobSeekerID
where m.Status == true && m.UserId == 1
select new { r.CompanyLogo, j.JobName, j.JobId, ur.UserId, r.JobSeekerID
, ur.FirstName, j.JobType, j.JobCareerLevel, j.JobLocation };
var list = query.Distinct().ToList();

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