change arguments order to resemble regular map

Change-Id: I57769bc73ae22ef1c0be4faefb684899e1ef03bb
check_op -> exists_op

Change-Id: Ib460129a61f63ae49f2515c3156c9d289b7ade3f
implement missing check for transaction

Change-Id: I254ab90cfcf8f86b096f9bf08f9a50a742bb06a4
transaction -> multi

Change-Id: If86d7d8262f332c30fbcc3cb9870cbf61cd3b9f3