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Automatic Acquisition of Locks A transaction T issues the standard read/write instruction, without explicit locking calls. The operation read(D)is processed as: if T;has a lock on D then read(D) else begin if necessary wait until no other transaction has a lock-X on D grant Tia lock-S on D; read(D) end Database System Concepts-6th Edition 15.9 @Silberschatz,Korth and SudarshanDatabase System Concepts - 6 15.9 ©Silberschatz, Korth and Sudarshan th Edition Automatic Acquisition of Locks A transaction Ti issues the standard read/write instruction, without explicit locking calls. The operation read(D) is processed as: if Ti has a lock on D then read(D) else begin if necessary wait until no other transaction has a lock-X on D grant Ti a lock-S on D; read(D) end
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