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When are two schedules said to be view equivalent?
Ans: Two schedules that is denoted as S and S' are said to be view equivalent if the subsequent three conditions are met
1) For every data item Q, if a transaction Ti reads the initial value of Q in schedule S, after that transaction Ti should in schedule S' also read the initial value of Q.
2) For every data item Q, if a transaction Ti executes read(Q) in schedule S and that value was generated by Tj (if any) , then transaction Ti must in schedule S' as well read the value of Q generated by Tj.
3) For every data item Q, if a transaction if any that carries out the final write(Q) in schedule S should perform the final write(Q) in schedule S'.
Attributes and its types explain?
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