Re: COALESCE()
Posted in 2012
Apart from any potential performance hit (which I can't explain, but in any
case a call to a procedure is naturally slower than "native" function), the
problem is that you have to define the number and type of arguments.
It would be nice and allow all kinds of user side improvements if we were
able to define a function that receives an unknown number of parameter and
also of unknown type.
I can see why this can't be done (function overload etc), but it surely
would help to implement this kind of stuff...
Any inside info from our architects?
Regards.
On Thu, Mar 22, 2012 at 9:17 AM, Stuart Brooks <stuart.brooks@ardenta.com>wrote:
> There isn't a COALESCE function in Informix and nested NVL functions is
> the alternative. You could write your own COALESCE stored procedure so
> that you don't have to change the SQL. But be aware there may potentially
> be a performance hit; queries in an application that I previously worked on
> showed poorer performance using a COALESCE stored procedure than when using
> nested NVLs.
>
> Regards
>
> Stuart
>
>
>
> ---
> Ardenta Ltd is a company registered in England and Wales. Registered
> number: 4181041. Registered office: Saxon House, Downside, Sunbury on
> Thames, Middlesex, TW16 6RT.
>
> -----Original Message-----
> From: informix-list-bounces@iiug.org [mailto:
> informix-list-bounces@iiug.org] On Behalf Of davidegrove@gmail.com
> Sent: 21 March 2012 19:26
> To: informix-list@iiug.org
> Subject: COALESCE()
>
> Isn't "COALESCE()" a SQL-92 function?
>
> Why it isn't in Informix (11.5).
>
> I suggested nested NVL functions as a work-around, but i would have
> preferred to just be able to have said, "It's in there."
>
> very happy to learn I was wrong.
>
> DG
>
>
> P.S. More whine with that cheese... I don't like continually having to be
> on defensive with our contractor.
>
> 1) Contractor: "What's the Informix equivalent to feature "X" in database
> "O" (or "SS")?"
> Me: "Sorry, Informix doesn't have it."
>
> 2) Contractor: "Why does dbexport/dbimport fail?"
> Me: "It's been a problem for a very long time, and IBM isn't going to fix
> it. There is a user-developed, non-IBM solution that is better, I suggest
> you use it."
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--
Fernando Nunes
Portugal
http://informix-technology.blogspot.com
My email works... but I don't check it frequently...