>>>>> "Chapman" == Chapman Flack <chap@anastigmatix.net> writes:
>> To clarify, I think my question is functions like json_each or
>> json_object_keys() are
>> set returning functions (
>> https://www.postgresql.org/docs/9.5/static/functions-srf.html),
>> which means it returns a set of results into a Datum.
Chapman> Well, it returns one result row as a Datum (either a single
Chapman> value or a tuple) each time it is called, until the whole set
Chapman> has been returned. The process is described here
Unfortunately that describes only one of the two calling protocols for
SRFs - the value-per-call mode, which as it happens is NOT the one that
json_each uses; that requires materialize mode, which is not actually
covered in the docs (but you can find examples in contrib/tablefunc).
--
Andrew (irc:RhodiumToad)