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 Ti a lock-S on D; read(D) end Database System Concepts-5th Edition,Oct 5,2006 16.12 ©Silberschat乜，Korth and SudarshanDatabase System Concepts - 5 16.12 ©Silberschatz, Korth and Sudarshan th Edition, Oct 5, 2006 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