Consider a schedule S of transactions T1 and T2:
|
T1 |
|
R(X) |
W(X) |
|
R(W) |
|
R(Z) |
|
commit |
|
|
T2 |
R(Y) |
|
|
R(Z) |
|
W(W) |
|
W(X) |
|
commit |
In the above transactions, R(X) stands for read data item X and W(X) stands for write data item Y. Also, WAW stands for write after write, and WAR stands write after read.
Which one of the following is false about the above schedule?
1
S is conflict serializable
2
Precedence graph of S is acyclic
3
Commit of T2 before commit of T1 is not allowed
4
WAW hazard is from T1 to T2