Jeff Davis wrote: > I have noticed that all SELECT queries alone in a transaction also > update pg_stat_database (I know it's just a view that calls > pg_stat_get_db_xact_commit()). The stuff in the stats collector is not stored on disk. Or, rather, it is, but not in the same way as regular tables; in particular, it's not fsynced. > Also, is there a way to retrieve the current transaction id? Some people like to write a C function calling GetTopTransactionId() to get it. If you want it for a quick experiment, you can create a temp table and examine pg_class.xmin for that table. -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc.
