Re: Writing SRF - Mailing list pgsql-general

From Tom Lane
Subject Re: Writing SRF
Date
Msg-id 20234.1272474058@sss.pgh.pa.us
Whole thread Raw
In response to Writing SRF  (Jorge Arevalo <jorgearevalo@gis4free.org>)
Responses Re: Writing SRF  (Jorge Arevalo <jorgearevalo@gis4free.org>)
List pgsql-general
Jorge Arevalo <jorgearevalo@gis4free.org> writes:
> I'm writing a SRF following the example from
> http://www.postgresql.org/docs/8.4/interactive/xfunc-c.html (section
> 34.9.10). In the example, in the code executed in first call, we get
> the number of tuples to be returned, and no more. Then, in each call,
> a new tuple is allocated and returned, until reach max_calls.

You don't have to do it that way, by any means.  max_calls is just
a field you can use if you feel like it --- it's not going to be
looked at by anything outside your SRF.  If you don't want to determine
the number of result rows at the start, just ignore max_calls, and
use whatever method is convenient to decide that you're done
returning rows.

            regards, tom lane

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