Re: loop with circular updates

Jessica M Salmon <jmsalmon@fs.fed.us> writes:
>       -is it true that when looping over query results in a plpgsql
> for..in..execute loop, several records are stored in memory at one time?

Yes, but that's got nothing to do with your issue.

>       -if I then update one of the records currently in memory, are these
> changes visible when the loop gets to it?

*All* queries in Postgres see a snapshot as of the instant of query
start.  This is a property of the MVCC rules and has nothing to do with
buffering.  What's returned by a FOR IN EXECUTE is whatever was in the
database when the loop began.

            regards, tom lane