Nested @Transactional in Repository a problem?

[Xaeras]

Since Arquillian apparently needs to run in a Transaction, the Transactional was added to all Repository-Classes. We don't quite know of the Side-Effects this has on the normal usecases, when the application is called via the REST-API.

These should be some of the questions that are to be answered:

• are there nested Transactions being created (is there even such a thing or is it always just one)
• if no:
• are there scenarios, where this could be a problem, if there is only one? (probably not)
• if yes:
• What happens to the "parent"-transaction, when the "Sub"-transaction fails
• If there are multiple "sub"-Transactions, what happens to the second one if the first one fails
• If there are multiple "sub"-Transactions, what happens to the first one if the second one fails
• And in general: Is this something you should avoid/is there another way?