JPA/Hibernate support for migration?

java hibernate jpa h2
willcodejavaforfood picture willcodejavaforfood · Oct 13, 2010 · Viewed 22.5k times · Source

I'm currently working on a desktop application using JPA/Hibernate to persist data in a H2 database. I'm curious what my options are if I need to make changes to the database schema in the future for some reason. Maybe I'll have to introduce new entities, remove them or just change the types of properties in an entity.

  • Is there support in JPA/Hibernate to do this?
  • Would I have to manually script a solution?

Answer

Henning picture Henning · Oct 13, 2010

I usually let Hibernate generate the DDL during development and then create a manual SQL migration script when deploying to the test server (which I later use for UAT and live servers as well).

The DDL generation in Hibernate does not offer support for data migration at all, if you only do as much as adding a non-null field, DDL generation cannot help you.

I have yet to find any truely useful migration abstraction to help with this.

There are a number of libraries (have a look at this SO question for examples), but when you're doing something like splitting an existing entity into a hierarchy using joined inheritance, you're always back to plain SQL.

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