1 votes 1 votes does graph based and time stamp ordering protocol ensure freedom from cascadeless rollback? Databases transaction-and-concurrency databases timestamp + – iarnav asked Dec 11, 2017 iarnav 1.4k views answer comment Share Follow See all 2 Comments See all 2 2 Comments reply abhishek tiwary commented Dec 11, 2017 reply Follow Share graph based protocol do not have rollback 0 votes 0 votes Shivansh Gupta commented Dec 11, 2017 reply Follow Share Not sure about Graph based. But TimeStamp Ordering based protocols may have Cascadeless Rollbacks, These are recoverability issues with the Basic Timestamp and Basic 2PL algorithms, which are removed by making the schedules strict. Hence Strict Timestamp Ordering and Strict 2PL does not have cascading rollbacks, but their basic versions may have. 2 votes 2 votes Please log in or register to add a comment.
Best answer 3 votes 3 votes Graph based protocol : the abort of a transaction can lead to cascading rollbacks Time stamp ordering protocol: Problem with timestamp-ordering protocol: suppose Tj read data item written by Ti if Ti is aborted, then Tj must abort further, any transaction that has read a data item written by Ti must abort This can lead to cascading rollback --- that is, a chain of rollbacks Both suffers from Cascading rollbacks. ref : http://codex.cs.yale.edu/avi/db-book/db4/slide-dir/ch16-2.pdf https://gateoverflow.in/49349/locking-protocol http://ggn.dronacharya.info/Mtech_CSE/Downloads/QuestionBank/ISem/Advanced_Database_Management_System/unit-2/Lec5.pdf MIRIYALA JEEVAN KUMA answered Jan 18, 2018 • selected Jan 18, 2018 by iarnav MIRIYALA JEEVAN KUMA comment Share Follow See all 0 reply Please log in or register to add a comment.
