| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Stephan Szabo <sszabo(at)megazone(dot)bigpanda(dot)com> |
| Cc: | Bruno Wolff III <bruno(at)wolff(dot)to>, Achilleus Mantzios <achill(at)matrix(dot)gatewaynet(dot)com>, email lists <lists(at)darrenmackay(dot)com>, pgsql-sql(at)postgresql(dot)org |
| Subject: | Re: query not using index for descending records? |
| Date: | 2004-01-29 17:24:14 |
| Message-ID: | 24411.1075397054@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-sql |
Stephan Szabo <sszabo(at)megazone(dot)bigpanda(dot)com> writes:
> I'd thought that I'd previously sent a message containing a set of
> definitions for the reverse opclasses (not meant for inclusion to the
> system because I was making SQL functions that basically did -<normal
> comparison function> to use as the function of the operator class, but
> possibly worth playing with) but now that I actually search again, I don't
> see it.
I don't recall having seen such a thing go by...
I fear that using SQL functions as comparators would only be useful for
proof-of-concept, not as an industrial-strength implementation. The
index code needs comparator functions not to leak memory, and I doubt
that that could be guaranteed with a SQL function. You'd probably have
speed issues too.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Joe Conway | 2004-01-29 17:52:46 | Re: How to retrieve N lines of a text field. |
| Previous Message | Achilleus Mantzios | 2004-01-29 16:50:41 | Re: java.lang.StringIndexOutOfBoundsException: String index |