MySQL experts joined DBTA's webinar, 'Best Practices for Accelerating your MySQL Data,' to examine architectural tips and best practices that can best support large-scale MySQL operations while ...

Running large, multi-table operations in a single transaction Let’s say you need to delete data from 10 tables as part of some operation.

In MySQL it's about 4 seconds vs. about 1.5 minutes. I believe MySQL is creating a temporary table with the entire contents of the subquery where as SQL Server's optimizer is doing something smarter.