State which of the following schedules are serializable.
a. r1(x) r2(y) r1(z ) r3(z ) r2(x) r1(y)
b. r1(x) w2(y) r1(z ) r3(z ) w2(x) r1(y)
c. r1(x) w2(y) r1(z ) r3(z ) w1(x) r2(y)
d. r1(x) r2(y) r1(z ) r3(z ) w1(x) w2(y)
e. r1(x) r2(y) w2(x) w3(x) w3(y) r1(y)
f. w1(x) r2(y) r1(z ) r3(z ) r1(x) w2(y)
g. r1(z ) w2(x) r2(z ) r2(y) w1(x) w3(z ) w1(y) r3(x)
a. Yes. all reads
b. No. T1 before T2 on x and after T2 on y
c. Yes
d. Yes
e. No. T1 before T2 and T2 before T3 on x; T2 before T3 and T3 before T1 on y.
f. Yes
g. Yes
You might also like to view...
Using Access can help managers make decisions because it can give data meaning
Indicate whether the statement is true or false
Answer the following statements true (T) or false (F)
1. When a recursive function directly calls itself, this is known as direct recursion. 2. Indirect recursion means that a function calls itself several times. 3. A recursive function cannot call a function other than itself. 4. Recursive algorithms tend to be less efficient than iterative algorithms.