Hi Thomas, all!
Thomas van Gulick wrote:
[[...]]
Test:
EXPLAIN SELECT * FROM t WHERE T="x";
Result: key T used
EXPLAIN SELECT * FROM t WHERE T!="x";
Result: key T _unused_
To be expected:
An "unequal" condition will evaluate to "true" for a very large
proportion of the index entries, so th
Hello list!
I've noticed in MySQL 5.0 partial keys on character fields aren't always
used. In 4.1 they were.
They seem not to be used when using inequality comparison.
I'm not sure whether this is a bug or intended (in the latter case I have to
work around it to get the speed I got with 4.1 ba
