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Two-Phase Locking

This approach [ Gray CACM ] locks data and assumes that a transaction is divided into a growing phase, in which locks are only acquired, and a shrinking phase, in which locks are only released. A transaction that tries to lock data that has been locked is forced to wait and may deadlock. The use of locks is illustrated in Figure 2.



Prasun Dewan
Wed Apr 7 11:52:42 EDT 1999