From: Terry Lee Tucker <terry@esc1.com>
Organization: Enhanced Solutions Computing
To: pgsql-sql@postgresql.org
Subject: Re: concatenation with a null column (using ||) nulls the result?
Date: Mon, 10 Apr 2006 18:03:53 -0400
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On Monday 10 April 2006 05:55 pm, Alvaro Herrera saith:
> Neil Harkins wrote:
> > Note: The cabinets_description for the "548-4th-Cab1" row is " ",
> > not NULL, hence it being displayed. Is this standard SQL behavior?
>
> Yes; something || NULL yields NULL.  If you want NULL to behave as ""
> for the purpose of the concatenation, try
>
> SELECT cabinets_name || ' - ' || COALESCE(cabinets_description, '') AS
> concat FROM cabinets WHERE cabinets_datacenters = 2;
>
> I'm assuming cabinets_name is NOT NULL, so it doesn't need COALESCE.
>
> --

Good to know. Thanks for the input...