Re: Arguments to foreign tables?

2012/11/6 Jeff Davis <pgsql@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
>
>
>
>
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