When to drop indexes
From: Chuck Hamilton <chuckh_at_dvol.com>
Date: 1996/05/29
Message-ID: <31ac452e.648005_at_n5.gbso.net>#1/1
Date: 1996/05/29
Message-ID: <31ac452e.648005_at_n5.gbso.net>#1/1
To drop indexes or not to drop indexes, that is the question.
When deleting or inserting a lot of rows for a table I've been told it's usually better to drop all it's indexes, make your changes, then rebuild the indexes. At what point does this become effective? Is there a rule of thumb for determining when it'll take more time to rebuild than to just leave them alone?
For example, suppose I have a snapshot that has approx 1 millions rows in it. There are only two indexes on the snapshot - the snapshot index proper, and a user created index. The snapshot log says there's 54,000 rows to be inserted. Should I drop the user index and rebuild it afterwards? Or should I leave it alone?
TIA
-- Chuck Hamilton chuckh_at_dvol.com Never share a foxhole with anyone braver than yourself!Received on Wed May 29 1996 - 00:00:00 CEST