Hi! Calling "SET TRANSACTION ISOLATION LEVEL ..." outside a transaction block has no effect. This is unlike "LOCK ..." and "DECLARE foo CURSOR FOR ...", which both raise an error. This is also unlike MySQL, where such a statement will affect the next transaction performed. There's some risk of data corruption, as a user might assume he's working on a snapshot, while in fact he's not.
I suggest issuing a warning, notice or error message when "SET TRANSACTION ..." is called outside a transaction block, possibly directing the user to the "SET SESSION CHARACTERISTICS AS TRANSACTION ..." syntax. I'm not familiar with the PostgreSQL source code, but it seems this would have to be added to check_XactIsoLevel() or by calling RequireTransactionChain() at some appropriate location. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
