Is Spring @Transactional required in read only database operations?

Question

I have a service, that only reads data from PostgreSQL DB (from replica, not master DB). In it's methods it can make several queries to DB. The classes and methods doesn't annotated by @Transactional. I thought that reading data from DB requires transactions too, that's why we put annotation @Transactional(readonly = true). Was I wrong? Stack: Java, Spring Boot 3

Yes you need a transaction and there will always be a transaction (on the db level), so you better control it. It might even speed things up as you will re-use the same connection to the db instead of acquiring a new one each time. — M. Deinum
– M. Deinum, Commented Feb 9, 2024 at 7:46

Grim · Accepted Answer · 2024-02-09 11:36:20Z

0

Some databases do not need a transaction to read data. Often they internally create a transaction for every query but wont tell you about that.

But reading in a transaction can give different results than reading WITHOUT a transaction.

Because: A transaction can have a locking. If your readonly-select-transaction "X" is optimistic-locking it might give changes that respect foregin insert-transactions "Y,Z" that reached savepoints and the readonly-transaction "X" assume optimisticly that "Y" an "Z" will finish successfully.

In this case the Select-Query in readonly-Transaction "X" gives results from insert-transaction "Y" and "Z" too but the same Select-Query without transactions will not contains the contributions of insert-transaction "Y" and "Z".

answered Feb 9, 2024 at 11:36

Grim

2,15312 gold badges63 silver badges139 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Is Spring @Transactional required in read only database operations?

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related