Question: a) A data item can be in only two states: locked or unlocked. Add lock and unlock instructions into the below T1 transaction. T1 Read

a) A data item can be in only two states: locked

a) A data item can be in only two states: locked or unlocked. Add lock and unlock instructions into the below T1 transaction. T1 Read X) X=X - 30 Write (X) Read (Y) Y=Y+10 (6 marks) b) State the three (3) serious problems may be caused by concurrent transaction execution

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