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Thread: 9.1: Slow to add range check on indexed column

9.1: Slow to add range check on indexed column

From
Moshe Jacobson
Date:
I just created a new partition in a log table, and then built a check constraint on the recorded timestamp column.

I have an index on this column, but the adding of the check constraint took a very, very long time. 

It seems that PostgreSQL 9.1 does not check the index when building a check constraint on an indexed column. Is this correct? Is this addressed in future releases?

Thanks.

--
Moshe Jacobson
Nead Werx, Inc. | Manager of Systems Engineering
2323 Cumberland Parkway, Suite 201 | Atlanta, GA 30339
moshe@neadwerx.com | www.neadwerx.com

"Quality is not an act, it is a habit." -- Aristotle

Re: 9.1: Slow to add range check on indexed column

From
Raymond O'Donnell
Date:
On 25/05/2013 20:37, Moshe Jacobson wrote:
> I just created a new partition in a log table, and then built a check
> constraint on the recorded timestamp column.
>
> I have an index on this column, but the adding of the check constraint
> took a very, very long time.
>
> It seems that PostgreSQL 9.1 does not check the index when building a
> check constraint on an indexed column. Is this correct? Is this
> addressed in future releases?

At a guess, I'd imagine that the check constraint has to be checked
against every row in the table, so the index would not be used anyway.

Ray.



--
Raymond O'Donnell :: Galway :: Ireland
rod@iol.ie