Module name: pgsql-server
Changes by: momjian(at)svr1(dot)postgresql(dot)org 04/04/19 22:00:27
> >> My question is whether postgres can index null values, and if not, do I
> >> have to accept a full table scan when locating records.
> > It indexes them, but "is null" is not an indexable operator, so you
> > can't directly solve the above with a 3-column index. What you can do
> > instead is use a partial index, for instance
> > create index i on CUSTOMER.WCCustOrderStatusLog (WCOrderStatusID)
> > where Acknowledged is null and Processing is null;
> That's a very nifty trick and exactly the sort of answer I was after!
Add CREATE INDEX doc mention of using partial indexes for IS NULL
indexing; idea from Tom.
pgsql-committers by date
|Next:||From: Bruce Momjian||Date: 2004-04-20 01:11:49|
|Subject: pgsql-server/doc/src/sgml filelist.sgml instal ...|
|Previous:||From: Bruce Momjian||Date: 2004-04-20 00:40:06|
|Subject: pgsql-server/src/bin Makefile pg_encoding/Make ...|