Thread: Transactions, stats and analyze (oh-my)
We have certain processes that import data then process and distribute the data. Since the processing looks primarily, but not exclusively, at the new records an ANALYZE prior to processing yields better plans. Although the table changes will trigger autovacuum to analyze the table this happens too late to be of use for the subsequent processing so we run an explicit analyze (which, when it collides with autovacuum, triggers a warning in the logs).
I would like to roll a number of steps into a transaction. What happens to the stats data generated by ANALYZE if the transaction is rolled back?
This message says the stats are reverted:
This implies they are not:
Cheers,
Steve
Steve Crawford <scrawford@pinpointresearch.com> writes: > I would like to roll a number of steps into a transaction. What happens to > the stats data generated by ANALYZE if the transaction is rolled back? > This message says the stats are reverted: > http://postgresql.nabble.com/Analyze-during-a-transaction-td5775069.html That's correct. They're just rows in a table, same as any other database data. > This implies they are not: > http://www.postgresql.org/message-id/E1XjbTw-0002f9-Ri@gemulon.postgresql.org That's about data in the pg_class row, which is a different thing from the pg_statistic data that you're worried about. regards, tom lane