Document that libpq's PQntuples() might overflow.

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index f98db479cd07c0c1e222652211ebd1b2b57a2d5f..7aa142800e7a92f5480f1e68299d8c4550fafcba 100644 (file)
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -1,4 +1,4 @@
-
+
 
 
  <application>libpq</application> - C Library
@@ -2092,7 +2092,9 @@ PGresult *PQdescribePortal(PGconn *conn, const char *portalName);
 
      
       
-       Returns the number of rows (tuples) in the query result.
+       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.
 
        
         int PQntuples(const PGresult *res);