Converting "is null" into a linq to sql statement

Posted by Darryl Braaten on Stack Overflow See other posts from Stack Overflow or by Darryl Braaten
Published on 2009-02-02T06:03:33Z Indexed on 2010/04/09 2:13 UTC
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linq-to-sql

I am having trouble replicating the following sql as a LINQ statement

select TableA.* from TableA left outer join TableAinTableB on TableA.Id = TableAId where TableBId is null

The following returns no lines

from TableA in db.TableA join AinB in db.TableAinTableB on TableA.Id equals TableAId where AinB.TableBId == null select TableA

Also tried and a few other things that didn't work.

from TableA in db.TableA join AinB in db.TableAinTableB on TableA.Id equals TableAId where AinB == null select TableA

TableAinTableB is a many to many table. The query I want will pull all the records from TableA that have no records in the middle table. My sql does what I want but I have no idea how to convert it to LINQ to SQL.

I ended up working around it by just doing a db.ExecuteQuery("working sql"); But I would like to know if the query is possible in LINQ and how to write it, or a pointer to a document that covers this scenario. My searching did not uncover anything I found useful.

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