| 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 | 
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| 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...
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