On Fri, Feb 19, 2010 at 11:58 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Robert Haas <robertmh...@gmail.com> writes: >> On Fri, Feb 19, 2010 at 11:33 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: >>> We can also fetch that tuple's >>> relfilenode and pass it to the subplan, which we do by setting the $0 >>> Param value before invoking the subplan. > >> Are the same tuples in scope when evaluating the expression that sets >> $0 as were in scope when evaluating ((b.oid)::integer + 1)? > > Yes, exactly the same. The parameter-value expression is just like any > other scalar expression that could appear where the SubPlan reference > is. It doesn't know anything about the subplan, really.
OK, thanks for the explanation. That makes more sense now. I've got to go study this some more before I ask my next question... ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers