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My database background comes from the Django framework (python). In Django, getting started with database migrations was easy: Django migrations. The Django framework provided tool for creating the migrations based on your models, and also a tool to apply the migrations on your database. I think this way of doing worked in both development and in production. You did not have to write migrations by yourself, the framework created them for you.

Now I have started a project with Spring Boot and Hibernate. I configure my application to use hibernate with JPA. With these settings, I now would need to know how does my framework handle database migrations? I mean if I change a column, either it's type, or even might remove it, then how do I migrate the database to the change? I know that spring boot will automatically detect column changes on startup, and create columns that do not exist based on the models (Entity's). I guess it has something to do with variable

spring.jpa.hibernate.ddl-auto

But how does it handle the existing database objects? Does it add the column to them too, and with what value? The default value I set? What if I change the column type? Can it then handle the change? These settings and spring-boot automated database management probably are not enough in the long run?

What I want to know is, that what are the best practices on how to handle database migrations with Spring Boot and hibernate combination? I believe there is a standard how most of the people with this combination handle the migrations? I hope it is as easy as with Django... I know about flyway, but don't know if I really need it, or if it is used much with this combination of mine (including spring boot and hibernate).

Ville Miekk-oja
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    Yes, Flyway and liquibase are both good database migration tools. The fact that you're using spring and hibernate is really irrelevant. If you need to migrate a database, they're good choices. ddl-auto is not a database migration tool. It just is a quick way of getting started and generate a schema from scratch, IMHO. Not something I'd ever use in production. – JB Nizet Jun 04 '17 at 10:04
  • hey whats the need of migration tool if ,we can create database and stuffs using hibernate-jpa – Ishan Garg Mar 22 '21 at 13:12

1 Answers1

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Liquibase or Flyway are the two main options for versioning/handling database migrations. ddl-auto is quick and dirty, but it does not, nor can it, take into account everything that needs to be handled. THere's also the chance of race-conditions (two instances trying to update the DDL at the same time).

This answer goes into more detail about ddl-auto in a production environment, and why you shouldn't.

Hibernate: hbm2ddl.auto=update in production?

https://www.credera.com/blog/technology-insights/java/liquibase-fed-inconsistent-schemas/ has bit more info on the why/concepts.

Darren Forsythe
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  • hey whats the need of migration tool if ,we can create database and stuffs using hibernate-jpa – Ishan Garg Mar 22 '21 at 13:10
  • Have you read the related question https://stackoverflow.com/questions/221379/hibernate-hbm2ddl-auto-update-in-production which should answer your question – Darren Forsythe Mar 22 '21 at 14:10