| From: | Stephan Szabo <sszabo(at)megazone23(dot)bigpanda(dot)com> |
|---|---|
| To: | Ian Burrell <ib(at)onsitetech(dot)com> |
| Cc: | <pgsql-sql(at)postgresql(dot)org> |
| Subject: | Re: Sorting by NULL values |
| Date: | 2003-03-04 20:13:05 |
| Message-ID: | 20030304120713.W55865-100000@megazone23.bigpanda.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-sql |
On Tue, 4 Mar 2003, Ian Burrell wrote:
> I am doing a query where I need to sort by a column that may be NULL
> because it is coming from an OUTER JOIN. I noticed a difference between
> PostgreSQL and other databases about where NULLs show up. It seems that
> with Postgres, NULLs are sorted after other values. Other databases
> sort them before.
> Is there any standard on how sorting NULLs work? Is there a way to
IIRC, they're either considered greater than or less than non-NULL values,
but the decision is up to the implementation.
> change Postgres's behavior? Is there a way to replace the NULLs with
> empty strings?
Coalesce should work.
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