Re: [HACKERS] Better default_statistics_target

-----BEGIN PGP SIGNED MESSAGE-----
Hash: RIPEMD160

> That was a pretty special case (LIKE/regex estimation), and we've since
> eliminated the threshold change in the LIKE/regex estimates anyway, so
> there's no longer any reason to pick 100 as opposed to any other number.
> So we're still back at "what's a good value and why?".

Glad to hear that, although I think this is only in HEAD, not backpatched,
right? Well at any rate, I withdraw my strong support for 100 and join in
the quest for a good number. The "anything but 10" campaign.

> I'm still concerned about the fact that eqjoinsel() is O(N^2). Show me
> some measurements demonstrating that a deep nest of equijoins doesn't
> get noticeably more expensive to plan --- preferably on a datatype with
> an expensive equality operator, eg numeric --- and I'm on board.

I hope someone else on the list can do this, because I can't. :)

- --
Greg Sabino Mullane greg@turnstep.com
PGP Key: 0x14964AC8 200806122054
http://biglumber.com/x/web?pk=2529DF6AB8F79407E94445B4BC9B906714964AC8
-----BEGIN PGP SIGNATURE-----

iEYEAREDAAYFAkhRxToACgkQvJuQZxSWSsj0OwCfel+zN/jQth79RvIHtxpUefQD
APMAmQEKIDS6BzqUjn4eTMzP9NDlxTbE
=JZTe
-----END PGP SIGNATURE-----

--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers