pt-online-schema-change won't work with backtick in default column value

[Bogdan]

Hello. Thanks for a great toolkit!

Experiencing following problem:

Trying to add an index online to MySQL Aurora table `users`.

Flags for command are `--alter-foreign-keys-method=rebuild_constraints --execute`.

I've simplified the copy of the target table for bugreport:

CREATE TABLE `test_users` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `tag` varchar(32) CHARACTER SET utf8mb4 DEFAULT NULL,
  `salt` varchar(50) NOT NULL DEFAULT '123`456',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 ROW_FORMAT=COMPACT

I'm adding an index for a field (tag), but getting this error:

The new table `foobar`.`_test_users_new` does not have a PRIMARY KEY or a unique index which is required for the DELETE trigger.

Obviously it does have a primary key on the table. What causing the problem is the backtick (grave accent) in the default value of `salt` (unrelated) column. Surprisingly, when removing it from the default value, error disappears.
Looks like table definition isn't parsed properly due to the backtick or something like that :)..

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PT-1447