From: | Paul Ganainm <paulsnewsgroups(at)hotmail(dot)com> |
---|---|
To: | pgsql-general(at)postgresql(dot)org |
Subject: | Re: Firebird and PostgreSQL at the DB Corral. |
Date: | 2003-12-18 03:53:04 |
Message-ID: | MPG.1a4b34f6158a44dd9896b7@news.gmane.org |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
kleptog(at)svana(dot)org says...
> A partial index is a index on a subset of a table. The case I can think of
> is a list of transactions, some of which are yet to be billed. They have a
> BillID field which is NULL. since this is the recent set it is queried quite
> often, so you can build an index like:
> CREATE INDEX x ON table ( customerid ) WHERE billid IS NULL
> Now an index can be used on customer when searching for only unbilled things
> whereas normally it would also have to search for all historical things as
> well.
> So, you get the benefit of a smaller index that is more useful to boot.
Hmmm... this is kinda like the Oracle thing where tables can be
partitioned? Sort of?
Paul...
--
plinehan x__AT__x yahoo x__DOT__x com
C++ Builder 5 SP1, Interbase 6.0.1.6 IBX 5.04 W2K Pro
Please do not top-post.
From | Date | Subject | |
---|---|---|---|
Next Message | John Sidney-Woollett | 2003-12-18 08:16:59 | Re: Replication |
Previous Message | Greg Sabino Mullane | 2003-12-18 02:36:29 | Re: sequences not renamed with tables |