Consider the following schedule S. read (T1. x), write(T2, x), write(T1, x), read(T3, x), commit (T1),...

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Consider the following schedule S. read (T1. x), write(T2, x), write(T1, x), read(T3, x), commit (T1), commit(T2), commit (T3) Questions: (a) (8 marks) briefly describe the concepts of lost update, unrepeatable read, dirty read. Are any of these present in the schedule above? If so, which ones? (b) (6 marks) draw a precedence graph of the schedule S. (c) (6 marks) is the schedule S conflict serialisable? If yes, why? If no, why not? U Consider the following schedule S. read (T1. x), write(T2, x), write(T1, x), read(T3, x), commit (T1), commit(T2), commit (T3) Questions: (a) (8 marks) briefly describe the concepts of lost update, unrepeatable read, dirty read. Are any of these present in the schedule above? If so, which ones? (b) (6 marks) draw a precedence graph of the schedule S. (c) (6 marks) is the schedule S conflict serialisable? If yes, why? If no, why not? U Consider the following schedule S. read (T1. x), write(T2, x), write(T1, x), read(T3, x), commit (T1), commit(T2), commit (T3) Questions: (a) (8 marks) briefly describe the concepts of lost update, unrepeatable read, dirty read. Are any of these present in the schedule above? If so, which ones? (b) (6 marks) draw a precedence graph of the schedule S. (c) (6 marks) is the schedule S conflict serialisable? If yes, why? If no, why not? U Consider the following schedule S. read (T1. x), write(T2, x), write(T1, x), read(T3, x), commit (T1), commit(T2), commit (T3) Questions: (a) (8 marks) briefly describe the concepts of lost update, unrepeatable read, dirty read. Are any of these present in the schedule above? If so, which ones? (b) (6 marks) draw a precedence graph of the schedule S. (c) (6 marks) is the schedule S conflict serialisable? If yes, why? If no, why not? U Consider the following schedule S. read (T1. x), write(T2, x), write(T1, x), read(T3, x), commit (T1), commit(T2), commit (T3) Questions: (a) (8 marks) briefly describe the concepts of lost update, unrepeatable read, dirty read. Are any of these present in the schedule above? If so, which ones? (b) (6 marks) draw a precedence graph of the schedule S. (c) (6 marks) is the schedule S conflict serialisable? If yes, why? If no, why not? U

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Sure lets address each question a Lost Update This occurs when one transaction overwrites the change... View the full answer