[Princeton]

The EXPLAIN data provides a lot of useful information and can help you in optimizing your queries.

The key is to learn how to interpret the EXPLAIN data.

TIP:

When creating any modification, query, etc, you should always build for large sites. This will help reduce problems and/or inquiries during the cycle of your modification.

"Testing" your modification on a small test site does not help .. your test site should have MANY members, MANY posts, MANY x rows so that you can actually see how effective your queries are.

Yes, it does help if you have access to a Big Board.
You can always create a script that will add fake members, fake posts, fake x etc for testing purposes.

Oh, no matter what I've read about these evil JOINS I was never able to understand how they work It's perhaps the only thing that I had such great difficulty understanding it

SirAdrian posted some excellent advice. :up: It's time to start learning.