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bpatel1
Posts: 8
Posted 07:03 Nov 23, 2013 |

Prof Sun,

                   Can you please upload or post undo and redo recovery log record that you explained in the class.

 

Thanks,

Beendal Patel.

cysun
Posts: 2935
Posted 17:50 Nov 23, 2013 |

Undo-only:

Start Transaction
<START, T>
Write(X, vx')
<UPDATE, T, X, vx>
Flush(log)
Write(Y, vy')
<UPDATE, T, Y, vy>
Flush(log)
Flush(X)
Flush(Y)
<COMMIT, T>
Flush(log)
Commit

Redo-only:

Start Transaction
<START, T>
Write(X, vx')
<UPDATE, T, X, vx'>
Write(Y, vy')
<UPDATE, T, Y, vy'>
<COMMIT, T>
Flush(log)
Commit
Flush(X)
Flush(Y)

Last edited by cysun at 17:51 Nov 23, 2013.