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From: Tom Lane <[email protected]>
To: Thomas Kellerer <[email protected]>
Cc: [email protected]
Subject: Re: (When) can a single SQL statement return multiple result sets?
Date: Thu, 11 Apr 2024 10:07:34 -0400
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
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Thomas Kellerer <[email protected]> writes:
> Tom Lane schrieb am 11.04.2024 um 01:02:
>> Jan Behrens <[email protected]> writes:
>>> While writing a PostgreSQL client library for Lua supporting
>>> Pipelining (using PQsendQueryParams), I have been wondering if there
>>> are any single SQL commands that return multiple result sets.

>> Right now, I don't think so.

> Hmm, what about functions returning multiple refcursors?

Sure, but let's distinguish between "here's an ugly workaround"
and "it just works".  Aside from being tedious, the refcursor
approach is restrictive: I don't think you can readily make
a refcursor on the result of INSERT/UPDATE/DELETE RETURNING,
nor on utility statements such as EXPLAIN.  (There might be
a way around the former restriction with WITH, but I'm
certain that won't work for EXPLAIN.)

			regards, tom lane

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