Dropping an index on a MyISAM table should be instantaneous. It should only take as long as deleting the idx file from the file system. But it's taking almost as long as creating the index itself!
Here's my queries and time they took:
/*[10:58:17 AM][367172 ms]*/ alter table MyTable add index (MyIndex)
/*[11:20:21 AM][183891 ms]*/ alter table MyTable drop index MyIndex
In MySQL, most ALTER TABLE operations involve a full reconstruction of the table, so dropping a key often takes almost as long as adding one. For a long time, optimizing them has not been a priority.
Also note that in MyISAM all keys are stored in one MYI file. So dropping a key is not as easy as just deleting a file.
-- Sasha Pachev AskSasha Linux Consulting http://www.asksasha.com
-- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
