Hibernate hbm2ddl.auto, possible values, and what they do

I am looking at the Hibernate hbm2ddl.auto configuration property and its possible values:

• validate
• update
• create
• create-drop

What do all these values do?

The Hibernate Reference Documentation only talks briefly about create-drop, but doesn't say anything about the other values:

hibernate.hbm2ddl.auto

Automatically validates or exports schema DDL to the database when the SessionFactory is created. With create-drop, the database schema will be dropped when the SessionFactory is closed explicitly.

e.g. validate | update | create | create-drop

I found very useful explanations in these Stack Overflow questions:

• Hibernate hbm2ddl.auto possible values and what they do?
• Schema is not dropped on hbmddl.auto = create.drop

But still nothing in the official documentation.

The link you provided is already the official documentation. So, there's nothing more official and comprehensive as-of today.

So I guess the answer to your question is two-fold:

• either file an enhancement request in the Hibernate issue tracker (better with a proposal)
• or read the corresponding code

I know this isn't the perfect answer you dreamt about, but this is actually all you have today.

But the good news is that the project is open-source, so you have all you need to help improve it :-).