0 votes 0 votes Consider the following schedule : S::r1(A),r3(D),w1(B),r2(B),r4(B),w2(C),r5(C),w4(E),r5(E),w5(B) The number of serial schedules which are view equal to schedule (S) ___________. Databases databases made-easy-test-series transaction-and-concurrency + – vnc asked Jan 10, 2017 edited Mar 6, 2019 by adeebafatima1 vnc 374 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes Transactions T1 and T3 are performing initial reads on items A and D respectively. Since they have no R/W conflict among them, they can be ordered in 2 ways. Transactions T2,T4 and T5 are performing final write on items C, E and B respectively in the said order. T2 and T4 do not have a R/W conflict among them. So they can be ordered in 2 ways. Therefore, total orderings = 2*2*1 = 4. Rahul Ranjan answered Jan 11, 2017 Rahul Ranjan comment Share Follow See 1 comment See all 1 1 comment reply reena_kandari commented Feb 1, 2017 reply Follow Share initial read are performed on A and D which are not going to change in the schedule so why to fix them at the intial stage.? 0 votes 0 votes Please log in or register to add a comment.