Help converting multi DB SQL Query to LINQ
I have the below SQL Query, which returns what I expect, and I would LIKE to accomplish the same thing in LINQ but so far my results have been less then spectacular. The major hurdle, as I see it, is that the data is coming from 3 separate DB's. I was able to 开发者_如何学Goaccomplish this in LINQ but it is extremely slow, see here.
So, with out further ado, here it is, with the hardcoded Guid() being the only exception as that gets passed in:
SELECT en.ClientID, p.LastName, p.FirstName, NurseName = dm2.FirstName + ' ' + dm2.LastName, SocialWorkerName = dm.FirstName + ' ' + dm.LastName, en.EnrollmentDate, en.DisenrollmentDate, ESWorkerName = sw.FirstName + ' ' + sw.LastName, sw.Phone
FROM CMO.dbo.tblCMOEnrollment en
LEFT OUTER JOIN CMO.dbo.tblSupportWorker sw
ON en.EconomicSupportWorkerID = sw.SupportWorkerID
INNER JOIN Connect.dbo.tblPerson p
ON en.ClientID = p.PersonID
LEFT OUTER JOIN aspnetdb.dbo.tblDemographics dm
ON en.CMOSocialWorkerID = dm.UserID
LEFT OUTER JOIN aspnetdb.dbo.tblDemographics dm2
ON en.CMONurseID = dm2.UserID
WHERE (en.CMOSocialWorkerID = '060632EE-BE09-4057-B17B-2D0190D0FF74'
OR
en.CMONurseID = '060632EE-BE09-4057-B17B-2D0190D0FF74')
AND (en.DisenrollmentDate IS NULL
OR
en.DisenrollmentDate > GetDate())
ORDER BY en.DisenrollmentDate, p.LastName
Since you want to issue 1 query, you should only use 1 datacontext. Add views to one of the databases to represent the other databases tables, then add it all to one LinqToSqlClasses file.
If you can't modify any of the three databases, create a fourth database with views to the other three.
精彩评论