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Conflict Serializable Schedule in DBMS

Conflict Serializable Schedule

When non-conflicting operations swap and transform into a serial schedule, the process is called conflict serializability.

Also, when the schedule is conflict equivalent, then only it is conflict serializable.

 

Operations of Conflicting

The operations are conflicting in the following conditions:

  1. Both are from different transactions.
  2. Both contain the same data.
  3. Both have minimum one write operation.

Example:

S1 and S2 should be equal logically for the swapping to take place.

 

 

Conflict Equivalent

The transformation from one to another takes place when conflicting operations swap in conflict equivalent. The above example shows S1 is conflict equivalent of S2, and their conversion can take place only if non-conflicting operations swap.

The schedules are conflict equivalent in the following cases:

  • Same transactions are there.
  • The order of the conflict operation is the same.

Example:

 

Schedule S2 is called serial schedule as first the operations of P1 are performed and then the operations of P2. The non-conflicting operations are swapped to transform schedule S1.

 

The final result after swapping S1 is:

 

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