We have a composite primary key consisting of column a, column b, column c. We don't have a lot of variation on column a and it makes sense for us to cluster by a. Our queries are SELECT column c FROM table WHERE column a=something and column e=something. By creating a composite secondary index on column e (column a and column e), we're thinking we can reduce the amount of seek on the index on column e.
My question is - is the column a value available already as bookmark lookups on single column index on e or would we better off creating a composite index on a and e if we always search by a and e? We're willing to accept some overhead on inserts for selects. Kyong -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql?unsub=arch...@jab.org
