libpq doc: Clarify what commands return PGRES_TUPLES_OK

The old text claimed that INSERT and UPDATE always return
PGRES_COMMAND_OK, but INSERT/UPDATE with RETURNING return
PGRES_TUPLES_OK.

Josh Kupershmidt
This commit is contained in:
Peter Eisentraut 2013-01-18 22:36:54 -05:00
parent c2a14bc7c9
commit fb197290c1

View File

@ -2469,7 +2469,8 @@ ExecStatusType PQresultStatus(const PGresult *res);
command that happens to retrieve zero rows still shows
<literal>PGRES_TUPLES_OK</literal>.
<literal>PGRES_COMMAND_OK</literal> is for commands that can never
return rows (<command>INSERT</command>, <command>UPDATE</command>,
return rows (<command>INSERT</command> or <command>UPDATE</command>
without a <literal>RETURNING</literal> clause,
etc.). A response of <literal>PGRES_EMPTY_QUERY</literal> might
indicate a bug in the client software.
</para>