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Distributed Database Management Systems: Lecture 28. The main topics covered in this chapter include: serializability theory; serializability theory in DDBS; equivalent schedules; serializable schedule; fragmented databases; replicated databases;...
Distributed Database Management Systems Lecture 28 In the previous lecture • Types of Transaction • Transaction in DDBS • Serial Transactions • Conflicting Ops/Tr In this Lecture • Serializability Theory • Serializability Theory in DDBS Equivalent Schedules Two schedules S1, S2 defined over same T are equivalent if they have same effect on the database, that is, leave database in same final state • Formally, if for each pair of conflicting operations Oij and Okl (i ≠ k) if Oij