On 8 March 2014 11:14, Simon Riggs <si...@2ndquadrant.com> wrote: > On 7 March 2014 09:04, Simon Riggs <si...@2ndquadrant.com> wrote: > >> The right thing to do here is to not push to the extremes. If we mess >> too much with the ruleutil stuff it will just be buggy. A more >> considered analysis in a later release is required for a full and >> complete approach. As I indicated earlier, an 80/20 solution is better >> for this release. >> >> Slimming down the patch, I've removed changes to lock levels for >> almost all variants. The only lock levels now reduced are those for >> VALIDATE, plus setting of relation and attribute level options. >> >> VALIDATE is implemented by calling pg_get_constraintdef_mvcc(), a >> slightly modified variant of pg_get_constraintdef that uses the >> transaction snapshot. I propose this rather than Noah's solution >> solely because this will allow any user to request the MVCC data, >> rather than implement a hack that only works for pg_dump. I will post >> the patch later today. > > Implemented in attached patch, v22 > > The following commands (only) are allowed with > ShareUpdateExclusiveLock, patch includes doc changes. > > ALTER TABLE ... VALIDATE CONSTRAINT constraint_name > covered by isolation test, plus verified manually with pg_dump > > ALTER TABLE ... ALTER COLUMN ... SET STATISTICS > ALTER TABLE ... ALTER COLUMN ... SET (...) > ALTER TABLE ... ALTER COLUMN ... RESET (...) > > ALTER TABLE ... CLUSTER ON ... > ALTER TABLE ... SET WITHOUT CLUSTER > ALTER TABLE ... SET (...) > covered by isolation test > > ALTER TABLE ... RESET (...) > > ALTER INDEX ... SET (...) > ALTER INDEX ... RESET (...) > > All other ALTER commands take AccessExclusiveLock > > I commend this patch to you for final review; I would like to commit > this in a few days.
I'm planning to commit this today at 1500UTC barring objections or negative reviews. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
