----- Original Message -----
From: "Michael Fuhr" <mike@fuhr.org>
To: "K Anderson" <msmouse@kittymail.com>
Subject: Re: [NOVICE] LOOping clobbering variable
Date: Sat, 1 Jan 2005 22:07:00 -0700

>
> On Sat, Jan 01, 2005 at 07:38:16PM -0800, K Anderson wrote:
>
> > The enclosed function returns a proper result only when the LOOP
> > and its enclosed functionality is removed from the function. Notice
> > near the return I have xml=xml||'</transaction>';
> >
> > That should at the least return what ever is in xml with
> > </transaction> concatinated, or so I would hope. But it's empty.
>
> I'd guess that one of the values you're concatenating is NULL.
> Concatenating NULL with anything results in NULL, so if you assign
> that back to xml then all subsequent concatenations will also result
> in NULL.
>
> You can use COALESCE to convert NULLs to empty strings.
Thanks Michael that did the trick. I still don't get it though. Seems like bad behavior to say the NULL||</transaction> results in NULL and not NULL</transaction> or even </transaction>.

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On Sun, Jan 02, 2005 at 03:06:08PM -0800, K Anderson wrote:
>
> Seems like bad behavior to say the NULL||</transaction> results
> in NULL and not NULL</transaction> or even </transaction>.

Others will disagree; take it up with the standards committee.

--
Michael Fuhr
http://www.fuhr.org/~mfuhr/

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