Salut Laurent_R,

Well, the thread is about MySQL, and I cannot speak about other RDBMS. But I did quote the documentation. Here's an example:

mysql> select bar, baz from foo;
+------+-------+
| bar  | baz   |
+------+-------+
| a    | qux   |
| b    | qux   |
| c    | qux   |
| d    | other |
+------+-------+
4 rows in set (0.00 sec)

mysql> update foo set bar = 'b' where baz = 'qux';
Query OK, 2 rows affected (0.02 sec)
Rows matched: 3  Changed: 2  Warnings: 0

mysql> select row_count();
+-------------+
| row_count() |
+-------------+
|           2 |
+-------------+
1 row in set (0.00 sec)
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But as we are discussing, you can't apparently get row_count() to return the changed rows with DBD::mysql.