Re: Using xmax to detect deleted rows

On 1/8/16 9:02 AM, Alvaro Herrera wrote:
> Meel Velliste wrote:
>> I would like to use the "xmax" column to detect rows that have been
>> recently deleted. Is it possible to get the deleted row versions with
>> non-zero xmax to remain visible long enough that I could periodically
>> check, say once an hour, and still be able to see rows that were deleted
>> since I last checked?
>
> No.  Maybe you want a trigger that saves the deleted row somewhere (a
> separate table perhaps) which you can later inspect and delete again?

If that is what you need then PgQ might be a good solution. But it'll be
a lot simpler to just do whatever you need to do when the row is
actually deleted. Just be sure you deal with rollbacks correctly if
you're doing something external.
--
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com