From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue, 29 Aug 2017 19:38:05 +0000 (-0400)
Subject: Doc: document libpq's restriction to INT_MAX rows in a PGresult.
X-Git-Tag: REL9_2_24~31
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2a82170a56cb5b7c8e8444d2089b15ba6492b102;p=thirdparty%2Fpostgresql.git

Doc: document libpq's restriction to INT_MAX rows in a PGresult.

As long as PQntuples, PQgetvalue, etc, use "int" for row numbers, we're
pretty much stuck with this limitation.  The documentation formerly stated
that the result of PQntuples "might overflow on 32-bit operating systems",
which is just nonsense: that's not where the overflow would happen, and
if you did reach an overflow it would not be on a 32-bit machine, because
you'd have OOM'd long since.

Discussion: https://postgr.es/m/CA+FnnTxyLWyjY1goewmJNxC==HQCCF4fKkoCTa9qR36oRAHDPw@mail.gmail.com
---

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 2412d3abd5f..13fdbaf2e20 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -2763,9 +2763,10 @@ void PQclear(PGresult *res);
 
      <listitem>
       <para>
-       Returns the number of rows (tuples) in the query result.  Because
-       it returns an integer result, large result sets might overflow the
-       return value on 32-bit operating systems.
+       Returns the number of rows (tuples) in the query result.
+       (Note that <structname>PGresult</> objects are limited to no more
+       than <literal>INT_MAX</> rows, so an <type>int</> result is
+       sufficient.)
 
 <synopsis>
 int PQntuples(const PGresult *res);