jdbc: Batch updates-Prepared Statements

Hello,

At postgresql JDBC driver a Statement.executeBatch() command
is equivalent to a transaction containing the update commands of the
batch. I think this is not compatible with java jdbc documentation
where states that when
an Statement.executeBatch() command is executed the batch of commands
are executed but no in a new transaction. If you want to create a new
transaction you have to state it explicitly. That is you should turn off
autocommit and finally execute the Connection.commit command.

According to current implementation I can't have multiple
Statement.executeBatch() commands in one transaction.

I also want to ask whether in postgresql JBDC driver 'Prepared statements'
are more efficient than 'Statements'.

thank you in advance.

Regards,
Sofia Alexaki