From: Tom Lane <tgl@sss.pgh.pa.us>
To: Igor Korot <ikorot01@gmail.com>
cc: Michael Paquier <michael.paquier@gmail.com>,
        pgsql-general <pgsql-general@postgresql.org>
Subject: Re: Retrieving query results
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Comments: In-reply-to Igor Korot <ikorot01@gmail.com>
	message dated "Thu, 24 Aug 2017 19:05:22 -0400"
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Date: Thu, 24 Aug 2017 19:18:47 -0400
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Igor Korot <ikorot01@gmail.com> writes:
> So there is no way to retrieve an arbitrary number of rows from the query?
> That sucks...

The restriction is on the number of rows in one PGresult, not the total
size of the query result.  You could use single-row mode, or use a cursor
and fetch some reasonable number of rows at a time.  If you try to inhale
all of a many-gigarow result at once, you're going to have OOM problems
anyway, even if you had the patience to wait for it.  So I don't think the
existence of a limit is a problem.  Failure to check it *is* a problem,
certainly.

			regards, tom lane


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