Robert Haas <robertmh...@gmail.com> writes: > I am fuzzy on the implementation details for making COPY act as a data > source for INSERT/SELECT though. I had thought to make EXPLAIN a data > source, but it turned out not to be possible (as far as I could tell) > without making EXPLAIN a fully-reserved word, which you vetoed. It > seems likely that COPY will present similar issues, though I haven't > tried.
IIRC the previous discussion touched on making it look like a set-returning function, although this would be a shade less convenient for option parsing etc. > I am also wondering what happens when someone embeds multiple COPY > statements in a single query, or sticks one inside of a CTE or on the > inner side of a left join. Yeah, it would need to be restricted somehow. A straight SRF function would materialize its result, but I doubt we want that to happen for COPY. (This brings up the whole question of performance impact, which would have to be thought about and minimized.) 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