Tom Lane <t...@sss.pgh.pa.us> wrote: > Kevin Grittner <kgri...@ymail.com> writes:
>> we acquire locks on all indexes even for a HOT UPDATE which uses >> a seqscan, and hold those until end of transaction. Is there a >> reason for that? > > Sounds dubious to me; although in the HOT code it might be that > there's no convenient place to release the index locks. Further testing shows that any UPDATE or DELETE statement acquires a RowExclusiveLock on every index on the table and holds it until end of transaction, whether or not any rows are affected and regardless of whether an index scan or a seqscan is used. In fact, just an EXPLAIN of an UPDATE or DELETE does so. It is only INSERT which releases the locks at the end of the statement. -- Kevin Grittner EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
