Strong recoverability in multidatabase systems

A multidatabase system (MDBS) consists of a number of multiple autonomous database management systems (DBMSs) in which global transactions are executed under the control of the MDBS, and local transactions are executed under the control of a local DBMS. Each local DBMS ensures local serializability. The function of the MDBS is to ensure global serializability. The major difficulty in ensuring global serializability stems from the fact that in the presence of local transactions, and without any restrictions on the local concurrency control of the participating local DBMSs., even serial execution of global transactions does not guarantee global serializability. These difficulties could be avoided if the serialization order of transactions were always the same as their commitment order. The authors study the class of transaction scheduling mechanisms in which transaction serialization order can be determined by controlling their commitment order. They use these results to design a multidatabase transaction management scheme that ensures global serializability