Re: line CASE statemelnt in query a la Oracle

On 09/08/10 10:05 PM, Dennis Gearon wrote:
> I would like to have a query replace a NULL in  a field with a truncated value from one field based on a size passed
in?
>
> Basically, I'd like to be able to generate a 'short title' for a record based on either the user's input for  a short
title,or a turncated 'normal title' at query time. 
>
> Would this be very expensive processor timewise?
>
> I might just feed the whole long title in and have the display properties of the browser truncate it.
>
>

shoudl be quite simple with coalesce...    say you have a short_title
field that might be null, and long_title is the full title...

     SELECT ...., COALESCE(short_title, SUBSTRING(long_title FOR $1)),....

where $1 is your passed in length.