Should I avoid using the annotation @Transactional when the transaction only reads data?

Question

I've migrated from old style of transaction management with TransactionProxyFactoryBean to a Declarative transaction management recommended by Spring to avoid exceptions with transactions that appear from time to time.

For transactions save update delete I added the annotation:

@Transactional(propagation = Propagation.REQUIRED, rollbackFor = Exception.class)

It works good for me.

The question is:

Should I avoid using the annotation @Transactional when the transaction only reads data?

Example:

public TradeData getTrade(long tradeId) throws Exception {
   return em.find(TradeData.class, tradeId);
}

After reading this article, which says:

"Better yet, just avoid using the @Transactional annotation altogether when doing read operations, as shown in Listing 10:"

I'm a little confused and I don't quite understand it.

Answer 1

For read-only operations with JDBC you don't need the @Transactional because it doesn't need a transaction, Hibernate does! So you can use @Transactional(readOnly = true). Then you are sure you don't update, delete, insert something by accident.

Answer 2

If a particular method of your service just read information from the database yes, you can put it as read-only

    @Transactional(readOnly = true)
    public Object yourReadOnlyMethod(){}