2010/11/18 Tom Lane <t...@sss.pgh.pa.us>: > Merlin Moncure <mmonc...@gmail.com> writes: >> On Wed, Nov 17, 2010 at 7:08 PM, Jaime Casanova <ja...@2ndquadrant.com> >> wrote: >>> i will start the review of this one... but before that sorry for >>> suggesting this a bit later but about using UNNEST as part of the >>> sintax? > >> Does for-in-array do what unnset does? > > Yes, which begs the question of why bother at all. AFAICS this patch > simply allows you to replace > > for x in select unnest(array_value) loop > > with > > for x in unnest array_value loop > > (plus or minus a parenthesis or so). I do not think we need to add a > bunch of code and create even more syntactic ambiguity (FOR loops are > already on the hairy edge of unparsability) to save people from writing > "select".
this patch is semantically equal to SELECT unnest(..), but it is evaluated as simple expression and does directly array unpacking and iteration, - so it means this fragment is significantly >>faster<<. Regards Pavel Stehule > > regards, tom lane > -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
