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Suppose a database schedule 5 involves transactions T1, T2, .............Tn Consider the precedence graph of S with vertices representing the transactions and edges representing the conflicts. If S is serializable, which one of the following orderings of the vertices of the precedence graph is guaranteed to yield a serial schedule ?

Suppose a database schedule 5 involves transactions T1, T2, .............Tn Consider the precedence graph of S with vertices representing the transactions and edges representing the conflicts. If S is serializable, which one of the following orderings of the vertices of the precedence graph is guaranteed to yield a serial schedule ? Correct Answer Topological order

The correct answer is option 1

Key Points

  • For a schedule to be conflict serializable, there should be no cycle present in the precedence graph.
  • Topological sort is not possible for the cyclic graph.
  • Hence topological ordering of the vertices is guaranteed to yield a serial schedule.

Additional Information

  • BFS and DFS are also possible for cyclic graphs.
  • Ascending order of transactions indices also does not guarantee serial a serial schedule because in a transaction more indices might come before the lower one.

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