My coworker and I are having an argument about whether it's necessary to VACUUM an insert-only table. My theory is that since there are no outdated nor deleted rows, VACUUM doesn't do anything. I just loaded a TRUNCATEd table with no indexes with 4 million records, indexed it, then ran VACUUM. There was nothing to do. So I don't see VACUUM as necessary with an insert-only table (not to be confused with ANALYZE, which clearly is necessary). My coworker is mainly going from the article at http://wiki.postgresql.org/wiki/Introduction_to_VACUUM,_ANALYZE,_EXPLAIN,_and_COUNT . In particular, the author says "Consider this scenario: a row is inserted into a table that has a couple indexes, and that transaction commits. Several updates happen on that row. Each update will create a new row in all indexes, even if the index key didn't change. And each update will also leave an old version of the row in the base table, one that has been updated to point to the location of the new version of the row that replaces it. " I don't get this at all. He starts by talking about inserts, but then talks only about updates (and VACUUM is clearly needed when rows are updated or deleted). Can someone disambiguate? adthanksvance ///ark
