On Fri, Jun 27, 2003 at 16:09:31 -0700, Matthew Hixson <hixson@poindextrose.org> wrote:
> Hi, I have a bunch of records that I need to delete from our database.
> These records represent shopping carts for visitors to our website.
> The shopping carts I'd like to delete are the ones without anything in
> them. Here is the schema:
IN is slow in 7.3.3 and below. It will be substantially faster in 7.4.
In the meantime rewriting your query to use not exists will probably
speed things up for you. Delete also allows for joins with other
tables which doesn't help in thsi particular case (at least not any
way I can think of), but is help for deleting items there are in
(as opposed to are not in) another table.