> But, to be honnest, I do not fully understand what is the action of
> setAutoCommit(true) when using a SELECT statement, which is not an
> update.
> Is it for transaction modes differents from TRANSACTION_NONE?

TRANSACTION_NONE is not supported in JayBird and Firebird. Lowest
transaction isolation level is TRANSACTION_READ_COMMITTED. However, if
you use TRANSACTION_REPEATABLE_READ, you have to commit after
executing SELECT in order to see committed chages (in other words you
have to start new transaction).

Also, you can create a selectable stored procedure that will
insert/update/delete some data during its execution. Committing will
fix the changes made by that procedure.

Best regards,
Roman Rokytskyy