Re: determine snapshot after obtaining locks for first statement - Mailing list pgsql-hackers

From Tom Lane
Subject Re: determine snapshot after obtaining locks for first statement
Date
Msg-id 3541.1261069199@sss.pgh.pa.us
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In response to Re: determine snapshot after obtaining locks for first statement  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
Responses Re: determine snapshot after obtaining locks for first statement  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
List pgsql-hackers
"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


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