Left Join outperforming Inner Join?

Question

I\'ve been profiling some queries in an application I\'m working on, and I came across a query that was retrieving more rows than necessary, the result set being trimmed dow

Answer 1

It's probably due to the INNER JOIN having to check each row in both tables to see if the column values (email in your case) match. The LEFT JOIN will return all from one table regardless. If it's indexed then it will know what to do faster too.