2012/11/6 Jeff Davis <pg...@j-davis.com>: > On Tue, 2012-11-06 at 09:19 +0100, Ronan Dunklau wrote: >> Maybe you could set some options on the foreign table before selecting >> from it ? >> Another way you could achieve the same result would be to give some >> column a special meaning (like it is done in the twitter_fdw for >> example). >> >> >> If you don't mind, do you have a specific use-case for this ? >> > Let's say that your remote data source is a stream of data that is not > actually being stored anywhere, e.g. network events. The data you want > to retrieve are all events with a timestamp less than X, and you assume > that the timestamp is monotonically increasing (so as soon as you get to > X, the read is finished). > > An SRF isn't good enough because it always materializes (and that's the > only way it allows you to control initialization and teardown of the > stream connection). But you don't want to have to define a new foreign > table each time. It would be better if there were a way to pass the > argument X to the FDW mechanism.
An SRF must not materialize always - depends on implementation Regards Pavel > > Regards, > Jeff Davis > > > > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
