Re: determine snapshot after obtaining locks for first statement

"Kevin Grittner" <Kevin.Grittner@wicourts.gov> writes:
> Thanks for the clarification.  That does not work for SERIALIZABLE
> at all, because other tables or rows referenced in that first
> statement would be using the original snapshot.  Indeed, the
> behavior under READ COMMITTED could be astonishing in certain
> circumstances as it breaks atomicity:

Yup.  That is stated fairly clearly already in the description of
READ COMMITTED mode, no?
http://developer.postgresql.org/pgdocs/postgres/transaction-iso.html#XACT-READ-COMMITTED
        regards, tom lane