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Middleware database replication techniques is a way to increase performance and fault tolerance without modifying the database management system (DBMS) internals. However, it introduces an additional overhead that may lead to poor response times. In this paper we present a modification of the optimistic two phase locking (O2PL) M.J. Carey et al. (1991) protocol that orders transactions by way of a deadlock prevention schema, instead of using the total order transaction delivery obtained by group communication systems (GCSs) G. Chockler et al. (2001) techniques, and do not need the 2 phase commit (2PC) rule P.A. Bernstein et al. (1987). We formalize its definition as a state transition system and show that it is 1-copy-serializable (1CS) P.A. Bernstein et al. (1987). |
