Mladen Gogala wrote:
> > 2) The sort of random I/O done by index lookups can be as much as 50X as
> > expensive on standard hard drives as sequential, if every block goes to
> > physical hardware.
> >
>
> Greg, how many questions about queries not using an index have you seen?
> There is a reason why people keep asking that. The sheer number of
> questions like that on this group should tell you that there is a
> problem there.
Very few of those reports found that an index scan was indeed faster ---
they just assumed so but when they actually tested it, they understood.
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ It's impossible for everything to be true. +
