I recently had an opportunity to migrate a customer from a physical server into Amazon’s RDS environment. In this particular case the customers’ platform makes extensive use of MySQL triggers and views. I came across two significant issues that prevented me from following Amazon’s documentation, which basically states “use mysqldump” but doesn’t call out a specific method of dealing with MySQL triggers and views.
Amazon Relational Database Service (Amazon RDS) is a great platform if you’re looking for complete hands-off management of your MySQL environment, but comes at a cost in the area of flexibility, i.e. you don’t have SUPER privilege and this brings up additional challenges.
#1 is easy, you simply make a configuration change within the Amazon RDS GUI on the node’s Parameter Group to set log_bin_trust_function_creators=1 and then a restart of your Amazon RDS node. The restart is required since without the SUPER privilege you lose access to changing DYNAMIC variables on the fly.
#2 is a little more complex. If you go with vanilla mysqldump (from say a 5.5 mysqldump binary) on a schema that has triggers and views, you will see error 1227, something like this:
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ERROR 1227 (42000) at line 27311: Access denied; you need (at least one of) the SUPER privilege(s) for this operation |
You’re seeing this message because MySQL in Amazon RDS doesn’t provide the SUPER privilege, and thus you cannot set up a trigger or view to run as a different user — only a user with SUPER can do that.
mysqldump will generate syntax for a trigger like this:
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DELIMITER ;;<br>/*!50003 CREATE*/ /*!50017 DEFINER=`root`@`%`*/ /*!50003 TRIGGER `after_insert_lead` AFTER INSERT ON `leads` FOR EACH ROW BEGIN<br>UPDATE analytics.mapping SET id_lead = NEW.id_lead WHERE mc_email = NEW.email;<br>END */;;<br>DELIMITER ; |
and for a view like this:
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/*!50001 CREATE ALGORITHM=UNDEFINED */<br>/*!50013 DEFINER=`web`@`%` SQL SECURITY DEFINER */<br>/*!50001 VIEW `admin_user_view` AS SELECT ... |
The problem is in the “DEFINER” lines.
Here’s one method that worked for me:
Here’s what my sed matches looked like:
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sed <br>-e 's//*!50017 DEFINER=`root`@`localhost`*///' <br>-e 's//*!50017 DEFINER=`root`@`%`*///' <br>-e 's//*!50017 DEFINER=`web`@`%`*///' <br>-e 's//*!50017 DEFINER=`cron`@`%`*///' <br>-e 's//*!50013 DEFINER=`cron`@`%` SQL SECURITY DEFINER *///' <br>-e 's//*!50013 DEFINER=`root`@`localhost` SQL SECURITY DEFINER *///' <br>-e 's//*!50013 DEFINER=`root`@`%` SQL SECURITY DEFINER *///' <br>-e 's//*!50013 DEFINER=`web`@`%` SQL SECURITY DEFINER *///' <br> |
Note: the example above won’t directly work due to WordPress “helpfully” stripping my text… you need to escape the forward slashes and asterisks.
A big caveat: this method is akin to a brute force method of getting your data into Amazon RDS — you’ve lost the elegance & security of running your triggers and views as separate defined users within the database — they are all now going to run as the user you loaded them in as. If this is a show-stopper for you, contact Percona and I’d be happy to take on your case and develop a more comprehensive solution. 🙂
Now all that’s left is to integrate this into your dump flow. Something like this should work:
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mysqldump <br>--host=source <br>| sed <br>-e ... lots of lines <br>| mysql <br>--host=destination |
I hope this helps someone!
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