Over a million developers have joined DZone.

Simple Database Migration in Java

DZone's Guide to

Simple Database Migration in Java

· Java Zone
Free Resource

Just released, a free O’Reilly book on Reactive Microsystems: The Evolution of Microservices at Scale. Brought to you in partnership with Lightbend.

As I started with Rails development I discovered the very neat feature of database migrations. For me this was the main advantage of using Rails compared to a pure Java solution.

In our Rails application this works without any problems: you can change the database schema as well as migrating the data itself via ruby.

I needed a similar feature at that time in Java and discovered Liquibase, which was relative easy to use and stable. But it has (in my opinion) one major drawback that you have to use xml and for your data migration you even have to use pure SQL. Then you’ll run fast into some issues (e.g. this). But okay, there is also one advantage over the Rails-mechanism: you don’t need to specify the rollback statement (if it is not pure SQL) – liquibase knows from the migration command which revert command it should use.

If you use Hibernate one could stick with SchemaUpdate, but several things don’t work properly with that approach.

Another idea would be to export objects from version 1 and import them into version 2 directly within your application logic e.g. with Groovy … or should I give DMT I try?

Now I thought that Grails could solve this issue better for Java, but to my knowledge (‘Automatic Database Migration’) there is not such a mature migration concept within Grails like in Rails. The Liquibase plugin (grails install-plugin liquibase) or the outdated (?) dbmigrate plugin (grails install-plugin dbmigrate) can solve this as well as autobase, which is based on liquibase too. Does somebody has experiences with that? Here is a mini comparison.

Today I discovered migrate4j, which seems to be the best tool I found so far for pure Java. Another option would be to use JRuby with Rails or simply rails, but this would be a bit of an architecture overkill for the most people, I fear.

Other choices might be:

Do you know other (better?) solutions? How do you do db migrations?

From http://karussell.wordpress.com/

Strategies and techniques for building scalable and resilient microservices to refactor a monolithic application step-by-step, a free O'Reilly book. Brought to you in partnership with Lightbend.


Opinions expressed by DZone contributors are their own.

{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}