Re: Arguments to foreign tables?

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.

Regards,
Jeff Davis