BTW, I was thinking that the DROP INDEX CONCURRENTLY logic needed to be: 1. Unset indisvalid, commit, wait out all reading transactions.
2. Unset indisready, commit, wait out all writing transactions. 3. Unset indislive, commit (with parent table relcache flush), wait out all reading-or-writing transactions. 4. Drop the index. However, I wonder whether we couldn't combine steps 2 and 3, ie once there are no readers of the index go directly to the "dead" state. I don't see a need for a period where the index isn't being inserted into but is still used for HOT-safety decisions. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers