Re: generate_series from now to infinity... - Mailing list pgsql-hackers

From Tom Lane
Subject Re: generate_series from now to infinity...
Date
Msg-id 29572.1242582802@sss.pgh.pa.us
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In response to Re: generate_series from now to infinity...  (hubert depesz lubaczewski <depesz@depesz.com>)
List pgsql-hackers
hubert depesz lubaczewski <depesz@depesz.com> writes:
> why is it not limiting generate_series in the second example?

nodeFunctionscan.c sucks the whole SRF output into a tuplestore before
returning any of it.  In principle you could do something different for
a value-per-call SRF, but it would require a second whole code path
(or else major refactoring of ExecMakeTableFunctionResult and related
code).  The performance implications are unclear too.

I seem to recall there was some discussion of this point when that code
was first written, but nobody bothered to do anything about it.
        regards, tom lane


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