It seems to me that it is inherently wrong to perform any operation on a database that depends on the order in which records are retrieved, without specifying that order in an ORDER BY clause. The "update t1 set f1 = f1 + 1" assumes that the operation will be performed in an order that guarantees that the highest unchanged record will be the next record processed. I don't believe that any database system should be required to support an action like this. RobR -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general