Add link to pt-table-checksum patch

Author: jacobbednarz

doc/rds.md

@@ -14,5 +14,16 @@ In Aurora replication, you have separate reader and writer endpoints however bec
 
 To work around this, you can follow along the [AWS replication between clusters documentation][aws_replication_docs] for Aurora with one small caveat. For the "Create a Snapshot of Your Replication Master" step, the binlog position is not available in the AWS console. You will need to issue the SQL query `SHOW SLAVE STATUS` or `aws rds describe-events` API call to get the correct position.
 
+#### Percona Toolkit
+
+If you use `pt-table-checksum` as a part of your data integrity checks, you might want to check out [this patch][percona_toolkit_patch] which will enable you to run `pt-table-checksum` with the `--no-binlog-format-check` flag and prevent errors like the following:
+
+```
+03-24T12:51:06 Failed to /*!50108 SET @@binlog_format := 'STATEMENT'*/: DBD::mysql::db do failed: Access denied; you need (at least one of) the SUPER privilege(s) for this operation [for Statement "/*!50108 SET @@binlog_format := 'STATEMENT'*/"] at pt-table-checksum line 9292.
+
+This tool requires binlog_format=STATEMENT, but the current binlog_format is set to ROW and an error occurred while attempting to change it.  If running MySQL 5.1.29 or newer, setting binlog_format requires the SUPER privilege.  You will need to manually set binlog_format to 'STATEMENT' before running this tool.
+```
+
 [migrate_test_on_replica_docs]: https://github.com/github/gh-ost/blob/master/doc/cheatsheet.md#c-migratetest-on-replica
-[aws_replication_docs]: http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Aurora.Overview.Replication.MySQLReplication.html
+[aws_replication_docs]: http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Aurora.Overview.Replication.MySQLReplication.html
+[percona_toolkit_patch]: https://github.com/jacobbednarz/percona-toolkit/commit/0271ba6a094da446a5e5bb8d99b5c26f1777f2b9