I had one case, with the same SQL server, where rewriting to a join made the query much faster. That was a data changing statement though, and I think the seman

I had one case, with the same SQL server, where rewriting to a join made the query much faster. That was a data changing statement though, and I think the semantics demanded it rerun the subselect. More recently, I've found that mysql sometimes behaves poorly with subselects, so I tend to avoid them out of habit.