On 7/12/07, Jerry Schwartz <jschwartz@the-infoshop.com> wrote:
> Since the "rows" is identical except for the last bit, where mine is 4 and
> yours is 2, does that mean yours is roughly more efficient by a 2:1 ratio?

For the most part, MySQL will do better with LEFT JOIN than an IN
subquery. You can read all about the subquery optimization issues on
Baron Schwartz's blog, xaprb.com. Here's one to get you started:
http://www.xaprb.com/blog/2006/04/30...oins-in-mysql/

- Perrin