(mongodb >=1.6.0)
MongoDB\Driver\Session::isInTransaction — Returns whether a multi-document transaction is in progress
Returns whether a multi-document transaction is currently in progress for this session. A transaction is considered "in progress" if it has been started but has not been committed or aborted.
У цієї функції немає параметрів.
Returns true if a transaction is currently in progress for this session,
and false otherwise.