The following bug has been SUBMITTED. ====================================================================== http://www.dbmail.org/mantis/bug_view_advanced_page.php?bug_id=0000171 ====================================================================== Reported By: OutboundIndex Assigned To: ====================================================================== Project: DBMail Bug ID: 171 Category: Database layer Reproducibility: always Severity: major Priority: normal Status: new ====================================================================== Date Submitted: 02-Feb-05 22:48 CET Last Modified: 02-Feb-05 22:48 CET ====================================================================== Summary: max() is indexable in mysql but not in postgresql causing extreme slowness every folder open Description: An often used sql query is fast on mysql (indexed) but unbearably horribly slow on postgresql once dbmail is full of a lot of messages (400,000 and maybe a lot less.) Particularly easy to feel when using squirrelmail. Postgresql cannot and does not use indexes on a min() or max() function. Blazingly fast performance in postgresql is restored by using the current value of the next sequence instead of max()+1 in the query. ======================================================================
Bug History Date Modified Username Field Change ====================================================================== 02-Feb-05 22:48OutboundIndex New Bug 02-Feb-05 22:48OutboundIndex File Added: pg-speed.diff ======================================================================
