Patent ID: 7421430

Claim:
A method of communicating a proposed database transaction in a multiple level database system having a plurality of mirror databases, comprising: receiving a token at a second mirror database of the plurality of mirror databases, the token comprising an indication of a lock reservation needed for the proposed database transaction in a first mirror database of the plurality of mirror databases, the proposed database transaction comprising a database transaction originating from a first mobile client, the first mobile client coupled to the first mirror database, the token indicating lock reservations needed for two or more transactions; evaluating the token to determine whether the lock reservation needed for the proposed database transaction conflicts with operations identified within a sync window of the second mirror database; setting a roll flag in the token in response to a conflict with operations identified within the sync window of the second mirror database, the roll flag instructing the first mirror database to roll back the proposed database transaction in the first mirror database; transmitting the token to a next mirror database of the plurality of mirror databases.