Re: <no subject>

From: "Daniel Schuchardt" <daniel_schuchardt(at)web(dot)de>
To: <pgsql-general(at)postgresql(dot)org>
Cc: <dev(at)archonet(dot)com>
Subject: Re: <no subject>
Date: 2003-10-01 10:19:01
Message-ID: 000001c38805$76576980$6500a8c0@DSVAIO
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

But CAST(NULL AS VARCHAR) should make it a varchar so i should be able
to || the both values. So perhaps a bug in CAST.

The only way here would be to make a CASE WHEN - i think thats not a
good behavoir.

Daniel

On Wednesday 01 October 2003 10:57, Daniel Schuchardt wrote:
> Hi @ all,
>
> I think thats a bug:
>
> SELECT '#' || '#'
>
> will work but
>
> SELECT '#' || CAST(NULL AS VARCHAR)

Nope - not a bug.

> will return only empty rows.
> My Query looks like this : SELECT field1 || field2 FROM ... If field2
> ISNULL then everything is null. CAST does not help.

Broadly speaking VALUE op NULL = NULL
You'll see similar issues with comparisons. You might find the article
below
useful:

http://techdocs.postgresql.org/guides/BriefGuideToNulls

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Stefan Leitich 2003-10-01 10:20:42 adressing column
Previous Message Richard Huxton 2003-10-01 10:07:43 Re: <no subject>