Does Heroku supports MySQL (esp. InnoDB database engine) ?
I see there is ClearDB add-on, but it didn’t state it supports InnoDB or not.
Heroku itself only provides direct support for PostgreSQL. Many applications (especially those in Rails) can be migrated from MySQL to PostgreSQL with little issue.
For situations in which you can’t easily migrate, you can use a third party Heroku add-on.
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