Thx, never though that this would be the issue. So one var in the ->where results in is null.

The where() method is used in the form where($column, $operator, $value), so for example where('reputation', '>', 10). If you're using the equals operator, you can just provide two arguments, e.g. where('user_id', 4).

Looking at the API for the method: https://github.com/laravel/framework/blob/4.2/src/Illuminate/Database/Query/Builder.php#L384, if you just provide column, the operator and value default to null. Further down in the method, there's a check to see if the value is null and converts the query into a proper "is null" condition (since using "field = null" won't work), so that seems consistent with the behaviour you are seeing.

So, as above, use whereRaw() since you want to perform a raw where query specific to the DBMS you're using, rather than the abstracted query builder.