On Wed, Oct 31, 2001 at 10:49:12PM +0000, Federico Schwindt wrote: > > thanks for the reply. it seems to be clear now. > > > MySQL Doesn't allow you to specifiy which index to use - it chooses > > (sometimes badly) whether or not to use one. > > From documentation: > > As of MySQL Version 3.23.12, you can give hints about which index > MySQL should use when retrieving information from a table. This is > useful if `EXPLAIN' shows that MySQL is using the wrong index. By > specifying `USE INDEX (key_list)', you can tell MySQL to use only > one of the specified indexes to find rows in the table. The > alternative syntax `IGNORE INDEX (key_list)' can be used to tell > MySQL to not use some particular index.
That should only be necessary in RARE cases, though. Jeremy -- Jeremy D. Zawodny, <[EMAIL PROTECTED]> Technical Yahoo - Yahoo Finance Desk: (408) 349-7878 Fax: (408) 349-5454 Cell: (408) 685-5936 MySQL 3.23.41-max: up 55 days, processed 1,243,268,204 queries (257/sec. avg) --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
