1 votes 1 votes Number of serial schedules but not conflict to schedule (S) S: r1(A),r2(A),r3(A),r4(A),w1(B),w2(B),w3(B),w4(B) Databases transaction-and-concurrency + – manisha11 asked Dec 17, 2018 manisha11 918 views answer comment Share Follow See all 2 Comments See all 2 2 Comments reply OneZero commented Dec 17, 2018 reply Follow Share do you mean the no.of serial schedules that are conflict equivalent to the above schedule? If thats your question then i got only 1 serial schedule : T1-T2-T3-T4 0 votes 0 votes flash12 commented Dec 18, 2018 reply Follow Share Please explain it.. 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes Number of serial schedules which are view equivalent to S but not conflict equivalent to schedule S Conflict equivalent Schedule is T1->T2->T3->T4 view equivalent Schedule are 1. first read same 2. final write same 3. w-R dependency on same on same data item T4 should be last bcz it is final write. T1,T2,T3 can be in any order for view equivalent. Here read operation doesn't matter bcz it is on single data item Answer is 3!-1=5 kavya kamish upadhya answered Dec 17, 2018 kavya kamish upadhya comment Share Follow See all 7 Comments See all 7 7 Comments reply Show 4 previous comments G4TE Hunter commented Dec 18, 2018 i edited by G4TE Hunter Dec 18, 2018 reply Follow Share Number of conflict equivalent schedule are w1->w2->w3->w4 in which r1,r2,r3,r4 arranged as 1x3x5x7x1=105 Number of view equivalent schedule are T1->T2->T3->T4 in which r1,r2,r3,r4 arranged as 1x3x5x7x3!=630 (3! for arranging w1->w2->w3->w4 as w4 is final write ) Then No of view equivalent which are not conflict equivalent schedule =630-105=525 Question need correction bcz Serial is subset of Conflict is subset of View 0 votes 0 votes MiNiPanda commented Dec 18, 2018 reply Follow Share @G4TE Hunter I understand your logic of finding conflict equivalent schedules..but what are you getting after 630-105? These are the no. of schedules which are only view equivalent and not conflict equivalent right? And what does the question ask for? 0 votes 0 votes manisha11 commented Dec 18, 2018 reply Follow Share @Shubhgupta the question had this description only. 0 votes 0 votes Please log in or register to add a comment.