Re: Partial Indices vs. mixing columns and functions

On Tue, Jul 17, 2001 at 11:10:13AM -0400, Tom Lane wrote:
> I think all you need is to add the correct implication rules to
> indxpath.c.  Let's see:

[snip]

They look fine. The IS NULL is a NullTest but I havn't looked into the
others yet. What confuses me about the pred_test group of functions is that
there's quite a bit of recursivness going on and two functions that are
almost the same. I can't see the point. And I don't understand the comments
at the beginnings of the functions :(

> BTW, it might be a good idea to split out the implication code into a
> new file, probably in optimizer/prep or optimizer/utils, rather than
> letting it continue to grow where it is.  Doesn't seem like it belongs
> in indxpath.c.

I keep wondering if there is not a better way of doing this. I prefer data
driven approaches yet this seems to produce more and more code as you add
new things.

--
Martijn van Oosterhout <kleptog@svana.org>
http://svana.org/kleptog/
> It would be nice if someone came up with a certification system that
> actually separated those who can barely regurgitate what they crammed over
> the last few weeks from those who command secret ninja networking powers.