On Wed, 02 Oct 2002 18:48:49 -0400, Tom Lane <tgl@sss.pgh.pa.us>
wrote:
>I don't think it's really a good idea to expect users to pick among
>multiple cost functions
The idea is that PG is shipped with a default representing the best of
our knowledge and users are not encouraged to change it. When a user
sends a "PG does not use my index" or "Why doesn't it scan
sequentially?" message to one of the support lists, we advise her/him
to set index_cost_algorithm to 3 (or whatever we feel appropriate) and
watch the feedback we get.
We don't risk anything, if the default is the current behaviour.
ServusManfred