Hibernate: hbm2ddl.auto=update in production?

Hibernate creators discourage doing so in a production environment in their book "Java Persistence with Hibernate":

WARNING: We've seen Hibernate users trying to use SchemaUpdate to update the schema of a production database automatically. This can quickly end in disaster and won't be allowed by your DBA.

We do it in production albeit with an application that's not mission critical and with no highly paid DBAs on staff. It's just one less manual process that's subject to human error - the application can detect the difference and do the right thing, plus you've presumably tested it in various development and test environments.

One caveat - in a clustered environment you may want to avoid it because multiple apps can come up at the same time and try to modify the schema which could be bad. Or put in some mechanism where only one instance is allowed to update the schema.

No, it's unsafe.

Despite the best efforts of the Hibernate team, you simply cannot rely on automatic updates in production. Write your own patches, review them with DBA, test them, then apply them manually.

Theoretically, if hbm2ddl update worked in development, it should work in production too. But in reality, it's not always the case.

Even if it worked OK, it may be sub-optimal. DBAs are paid that much for a reason.