HibernateTemplate fall back to auto-commit, where?

Question

HibernateTemplate api says:

...its capability to fall back to 'auto-commit' style behavior when used outside of transactions

http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/orm/hibernate3/HibernateTemplate.html

Can anyone please point out where that happens:

https://github.com/

http://grepcode.com

I searched for like an hour with no success. I'm looking for the answer for when transactions are created in my app, as I understand hibernate demands a transaction to be open for every interaction with db but I don't open any transaction neither I use JTA and I still have reading operations working fine.

Answer 1

All database statements are executed within the context of a physical transaction , even when we don't explicitly declare transaction boundaries (BEGIN/COMMIT/ROLLBACK). Data integrity is enforced by the ACID properties of database transactions .

So if you don't enrol your current unit of work in the context of a logical transaction (Spring transaction interceptor), then each DB statement will execute in a separate database physical transaction, hence you are going to run in "auto-commit" mode.

...its capability to fall back to 'auto-commit' style behavior when used outside of transactions

This phrase tell you that you can use TransactionTemplate from within a @Transactional context and even without a transaction context as well. So you are not obliged to use the Spring transaction demarcation, although for performance reasons you should do so .

So your TransactionTemplate related code works independently of having or not having a currently running transaction context.

With plain-old JDBC your code must explicitly declare a transaction boundary (begin/commit/rollback) if you want to enroll multiple statements in a single database transaction. If you don't do that you will run in "auto-commit" mode.