docs: note that changedRows is English-only

closes #1820

Readme.md

@@ -855,6 +855,10 @@ You can get the number of changed rows from an update statement.
 "changedRows" differs from "affectedRows" in that it does not count updated rows
 whose values were not changed.
 
+**Note** this value is parsed from the server message and only works with an English
+response. If your mysql server's install is in a different language, use
+[affectedRows](#getting-the-number-of-affected-rows).
+
 ```js
 connection.query('UPDATE posts SET ...', function (error, results, fields) {
   if (error) throw error;