coalesce a null to a char ?

Started by Gauthier, Daveabout 17 years ago2 messagesgeneral
Jump to latest
#1Gauthier, Dave
dave.gauthier@intel.com

How can I do this....

selcet coalesce((select 'y' from foo where name = f.name),'n') from foo f where...

So the query returns a "y" or "n" depending on whether or not the subquery is null.

I get...

"ERROR: failed to find conversion function from unknown to text"

In reply to: Gauthier, Dave (#1)
Re: coalesce a null to a char ?

On 06/04/2009 22:55, Gauthier, Dave wrote:

How can I do this....

selcet coalesce((select 'y' from foo where name = f.name),'n') from foo f where...

So the query returns a "y" or "n" depending on whether or not the subquery is null.

Are you sure that the subquery is returning any rows? Try something like
this instead (not tested):

select
case
when exists(select 1 from foo where name = f.name) then 'y'
else 'n'
end
from foo....

Ray.

------------------------------------------------------------------
Raymond O'Donnell, Director of Music, Galway Cathedral, Ireland
rod@iol.ie
Galway Cathedral Recitals: http://www.galwaycathedral.org/recitals
------------------------------------------------------------------