LIKE '%foo%' (was: mysql is a ...)

[Frederik Lindberg]

On Sun, 14 Nov 1999, Michael Widenius wrote:

> Frederik> internals. Maybe it is very easy to speed up the index scan, or maybe
> Frederik> MySQL incorrectly decides that the index is worthless (even though a
> Frederik> complete index scan is cheaper than a complete data scan).
> 
> The above isn't really true;  If the records are short, it's faster to 
> scan the table than scan the index (as scanning the index involves
> much more seeks)

Yes. I'm usually assuming that the index fits and is cached in memory, but
the table itself is too big.

Back to the original problem: Is there a way to optimized LIKE '%foo%'?


-Sincerely, Fred

Fred Lindberg, Inf. Dis., WashU, St. Louis, MO, USA