Re: argument of CASE/WHEN must not return a set - Mailing list pgsql-general

On Thu, Jan 9, 2014 at 1:26 AM, George Weaver <gweaver@shaw.ca> wrote:

ARRAY_TO_STRING(  REGEXP_MATCHES('12-70510','^[0-9,0-9.0-9]+')
development(#                                  , ',')

I guess this part of your statement will return 1,2, which is a set

Can you try below:

SELECT CASE

             WHEN LENGTH(ARRAY_TO_STRING(  REGEXP_MATCHES('12-70510','^[0-9,0-9.0-9]+')

                                         , ',')

                         )

                  = LENGTH('12-70510')

             THEN cast(ARRAY_TO_STRING(  REGEXP_MATCHES('12-70510','^[0-9,0-9.0-9]+')

                                  , ',') as varchar(100))

             ELSE ''

         END AS "12-70510";

But anyways, I think the best way to do it is the way you have already figured (check the plan for both statements once you have sorted out the error)

Best Regards,
Sameer Kumar | Database Consultant
ASHNIK PTE. LTD.
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