We have 2 transactions. T1: withdraw $50 and T2: withdraw $100. We consider concurrent executions of the transactions. Which schedule(s) is (are) serializable? Explain why.
T1 reads the balance.
T2 withdraw $100.
T1 withdraw $50.
T2 withdraw $100.
T1 reads the balance.
T1 withdraw $50.
T1 reads the balance.
T2 withdraw $100.
T1 withdraw $50.
to check for the serializability one must draw a precedense graph of transaction and check if there is any loop in graph the it is not serializable .
the graph contain vertex as no of different transaction and edges are drawn if any conflicts are found .
various conflicts are :
1] read -write
2] write- read
3] write-write
** TEXT GIVEN IN QUESTION IS CONVERTED INTO TABLE:
so ,
for drawing vertex stand in one coloumn and find the conflict in another coloumn and if found draw a vertex. dont found conflict in same coloumn.
Transactions. Consider an ATM system. We have 2 transactions. T1: withdraw $50 and T2: withdraw $100....
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