Answer 1

There is no practical difference here, since you aren't changing any data. The query you execute will generate an SQL select. Transactions are there to allow you to apply ACID properties to a collection of inserts, updates, etc.

However, if you begin manipulating the objects in the list returned from this method, calling setters, etc. those changes will be propagated back to the database out-with a transaction on an ad-hoc basis. In other words you'll effectively be working with the db in auto-commit mode. This is unlikely to be what you want.

The important thing to understand is that the duration of a persistence context and a transaction can be managed separately. Often though you would want to manage them together.

Answered by: Lily708 | Posted: 01-03-2022

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