How often do you need to check and optimize your database?

So far I've only been checking and optimizing my database tables every few months, or if there's a noticeable problem. I had read that it was best not to repair/optimize them if the overhead was only a few kb, so I only repair the ones that are 5kb or larger. What's your procedure?

 

Repair? I never do unless it reports that there is a crashed table. I haven't had a crashed table in years because I primarily use InnoDB.

Optimize? Only when you delete large quantities of data from your database. It provides no benefit otherwise.