Gate2020 cs Q61
0. Consider a schedule of transactions T1 and T2:
| T1 | RA | RC | WD | WB | Commit | |||||
| T2 | RB | WB | RD | WC | Commit |
Here, RX stands for “Read(X)” and WX stands for “Write(X)”. Which one following schedules is conflict equivalent to the above schedule?
- Option : D
- Explanation : R2(B) is conflicting with W1(B) so, W1(B) should always come after R2(B)W2(B) is conflicting with W1(B) similarly, W1(B) should always come after W2(B)R2(D) is conflicting with W1(D), so, W1(D) should always come after R2(D)R1(C) is conflicting with W2(C) so, W2(C) should always come after R1(C)Therefore the transaction will be:
T1 T2 R(B) W(B) R(D) R(A) R(C) W(D) W(B) W(C) Commit Commit
