Why the transactions schedule below is violating two- phase policy? Database Concurrency Control Two-Phase Locking Techn

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Why The Transactions Schedule Below Is Violating Two Phase Policy Database Concurrency Control Two Phase Locking Techn 1 (22.77 KiB) Viewed 56 times

Why the transactions schedule below is violating two- phase policy? Database Concurrency Control Two-Phase Locking Techniques: The algorithm T1 T2 Result read lock (Y): X=50; Y=50 read item (Y); Nonserializable because it. unlock (Y); violated two-phase policy read_lock (X); read item (X); Time unlock (X): write_lock (Y); read item (9) Y:=X+Y; write_item (Y); unlock (Y): write_lock (x): read item (X): X=X+Y: write_item (X); unlock (x);