C# Lambda Join with an OR condition-CodePudding

Is it possible to translate this SQL statement into C# lambda syntax?

SELECT *
FROM Table1 t1
INNER JOIN Table2 t2 on t1.Table1_ID = t2.Table1_ID
    OR t1.Some_Other_Column = NULL

For the C# syntax I would do something like this:

context.Table1
    .Join(context.Table2,
        t1 => t1.Table1_ID,
        t2 => t2.Table1_ID,
        (t1, t2) => new { t1, t2 }
    .Select(x => new 
    {
        // start listing out properties here:
        x.t1.first_column,
        x.t1.last_column,
        x.t2.first_column,
        // and so on
    }).ToList();

I'm just not sure how to include the condition: OR t1.Some_Other_Column = NULL into the above statement. Any help would be appreciated.

CodePudding user response：

Not with the Join LINQ operator as it only supports equality for the join expression.

You could do this via a where operation, how a LINQ provider translates this will depend on the provider:

source1.SelectMany(x => source2.Select(y => new { x, y })
       .Where(v => v.x.Prop1 = v.y.Prop1
                || v.x.Prop2 is null)