2 votes 2 votes i am finding difficulty in view serializable schedule please tell me how to check view serializablity with polygraph Databases databases transaction-and-concurrency + – Shivani gaikawad asked Oct 27, 2018 Shivani gaikawad 1.0k views answer comment Share Follow See all 12 Comments See all 12 12 Comments reply Shobhit Joshi commented Oct 27, 2018 i edited by Shobhit Joshi Oct 27, 2018 reply Follow Share $T1$ $ T2$ $R(X)$ $R(X)$ $W(X)$ $R(Y)$ $W(X)$ $W(Y)$ $W(Y)$ $W(Y)$ The Schedule S will look like the above with 2 transactions $T1$ and $T2$. There is a $RW$ conflict at $row$ $1$ and $row$ $3$. So $T1\rightarrow T2$ and a $RW$ on $row$ $2$ and $row$ $5$. So, $T2\rightarrow T1$. So, this is not $conflict$ $serializable$ as it contains a cycle. A $view$ $serializable$ schedule which is not conflict-serializable contains a $blind write$. This schedule contains a blind write. So, this is $view$ $serializable$. 0 votes 0 votes Shivani gaikawad commented Oct 27, 2018 reply Follow Share @shobit there is blind write W(Y) in t1 0 votes 0 votes Shobhit Joshi commented Oct 27, 2018 reply Follow Share W(Y) is not in t1 0 votes 0 votes Prince Sindhiya commented Oct 27, 2018 reply Follow Share @Shobit Bhai W1(y) is given so it is in T1 0 votes 0 votes Shobhit Joshi commented Oct 27, 2018 reply Follow Share ohh i missed it .... i will change it .. Thanks for correcting me 0 votes 0 votes Shivani gaikawad commented Oct 27, 2018 reply Follow Share can anyone explain how to draw polygraph for checking view serializability 0 votes 0 votes Shobhit Joshi commented Oct 28, 2018 reply Follow Share checking for view serializability is a NP complete problem. 0 votes 0 votes altamash commented Oct 28, 2018 i moved by altamash Oct 28, 2018 reply Follow Share please correct me if iam wrong 0 votes 0 votes altamash commented Oct 28, 2018 reply Follow Share or check this example 1 votes 1 votes Shivani gaikawad commented Oct 28, 2018 reply Follow Share it is given that it is not view serializable 0 votes 0 votes altamash commented Oct 29, 2018 reply Follow Share this was a example to find view serializable. not and extact answer .answer should be only s4. 0 votes 0 votes Shivani gaikawad commented Nov 1, 2018 reply Follow Share @altamash read the comment below the question, i have asked the question to know the view serializability , I know that it is not serializable but my doubt is how to check view serializability using polygraph for these question 0 votes 0 votes Please log in or register to add a comment.