GATE2015-2-46
Consider a simple checkpointing protocol and the following set of operations in the log. (start, T4); (write, T4, y, 2, 3); (start, T1); (commit, T4); (write, T1, z, 5, 7); (checkpoint); (start, T2); (write, T2, x, 1, 9); (commit, T2); (start, T3); (write, T3, z, ... list? Undo: T3, T1; Redo: T2 Undo: T3, T1; Redo: T2, T4 Undo: none; Redo: T2, T4, T3, T1 Undo: T3, T1, T4; Redo: T2
Consider a simple checkpointing protocol and the following set of operations in the log. (start, T4); (write, T4, y, 2, 3); (start, T1); (commit, T4); (write, T1, z, 5, 7); (checkpoint); (start, T2); (write, T2, x, 1, 9); (commit, T2); (start, T3); (write, T3, z, 7, 2); ... the redo list? Undo: T3, T1; Redo: T2 Undo: T3, T1; Redo: T2, T4 Undo: none; Redo: T2, T4, T3, T1 Undo: T3, T1, T4; Redo: T2
answered
Nov 10, 2017
in Databases
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