One Query Compared to Three
 

Is there a large difference between running three queries or one?

I have a script I wrote, and I can do it in three queries and it works perfectly -- I think I can do it in one (or maybe two) if I thought it out a little more ... however, that would be a lot of joins and some other stuff.

My question is ... from a load standpoint ... is there a really significant reason to change it and do it in one instead?

Just curious what everyone thought.

It depends on how often those queries are going to be run. If they get run on every thread and you have 3000 users on the site at a time, that could add up. However, if it is only run on your members page and you only have 10 users on at a time, it will probably make no difference at all.

Usually if you can combine the queries with joins - you should. MySQL is efficient at joining relational tables.