Message-ID: <e5116f96a53b73c1f3dff05d35218d146e622262.camel@datenzone.de>
Subject: Better documentation for row_number() combined with set returning
 functions
From: Erik Tews <erik@datenzone.de>
To: pgsql-docs@lists.postgresql.org
Date: Tue, 25 Feb 2020 20:24:13 +0100
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Hi

The current documentation of Postgresql sounds like row_number() over
() can be used to number the rows returned by postgres. However, that
doesn't work when the query also uses set returning functions such as
json_array_elements. In this case, row_number() will be the same for
every element of the set.

I suggest to add a paragraph to the description of row_number() that
states that this is the behaviour and maybe also reference the "with
ordinality" feature that can be used instead.

Erik

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