Umm... What? The call to 'currval' will most certainly do exactly what is intended by the code. Because any call to currval returns the database _session's_ notion of the most recent squence value, Postgres will return whatever the last call to nextval (including column's DEFAULT constraint) returned *only for that session*. And because the INSERT and SELECT statements are in a single string there is no chance of another call to nextval between the INSERT and SELECT.