Andrew Dunstan <and...@dunslane.net> writes: > Perhaps my understanding of when XIDs are acquired is insufficient. When > exactly is it optional?
My understanding of Noah's comment is that we would be exposing what used to be an optimisation only implementation detail to the user, and so we would need to properly document the current situation and would probably be forbidden to change it in the future. Then I guess it's back to the use cases: do we have use cases where it would be interesting for the pre-commit trigger to only get fired when an XID has been consumed? I don't think so, because IIRC CREATE TEMP TABLE will consume an XID even in an otherwise read-only transaction, and maybe the TEMP TABLE writes will not be considered "actual writes" by the confused user. What about specifying what notion of "data modifying" transactions you're interested into and providing an SQL callable C function that the trigger user might then use, or even a new WHEN clause? Regards, -- Dimitri Fontaine http://2ndQuadrant.fr PostgreSQL : Expertise, Formation et Support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
