Should I ever use @Transactional on a Service class

Question

I have a web application that uses Spring NamedJDBCTemplate, and all the calls to database are select statements.

In this case should i use @Transactional in my service class that calls the DAO class that inturn fires select statements to DB.

According to Transaction statergies listing 10 suggests to not use @Transactional for reads. Will i be bringing an overhead by using @Transactional and also i dont want to miss the AOP advises that i can bring in for @Transactional in future.

Answer 1

Yes, you should always access the database from inside a transaction. Not doing it will in fact create a transaction for every select statements.

Transactions aren't just useful for atomicity of updates. They also provide isolation guarantees. For example, (depending on the isolation level) reading the same row twice in a single transaction can return you the same data, and thus make sure you don't have incoherences in the read data. Doing it with multiple transactions won't provide any such guarantee.