LINQ join with OR

Question

I want to do a JOIN with LINQ using an OR statement.

Here is the SQL query I\'m starting with:

SELECT  t.id
FROM Teams t
INNER JOIN Games g 
   ON (g         


        

Answer 1

The where clause applies a boolean condition, so using "||" is the way to go. You can chain multiple where clauses but I believe that will give you a "and" operation, rather than an "or".

Answer 2

I struggled with this as well until I found the following solution, which worked well for my situation:

var y = from t in db.Teams
        from g in db.Games
        where
        (
            t.ID == g.AwayTeamID
            || t.ID == g.HomeTeamID
        )
           && g.WinningTeamID != 0
           && g.Year == year
        group t by t.ID into grouping
        select grouping;

Under the covers, your solution probably works very close to this one. However, I bet this one is just a bit faster if you benchmark it since it is not JOINING every item in the first dataset with every item in the second dataset, which could be a disaster if either (or both) dataset were really big.