Conflict Serializability

There are two types of conflicts. In this article, we are going to learn about Conflict Serializability. Before that, let’s see what both the conflicts are.

Conflict Equivalent: If a schedule-S can be transformed into a schedule-S’ by a series of non-conflicting instructions, then S and S’ are said to be ‘Conflict equivalent’.

Conflict Serializable: A schedule-S is said to be ‘conflict serializable’, if it is conflict equivalent to a serial schedule.

Example-1:   Create schedule-5 which is equivalent to schedule-3 part 3 of Transaction Isolation.

By swapping the 4 and 5 instructions which are non-conflicting, we can get:

By swapping the 5 and 6 instructions which are non-conflicting, we can get schedule-6 (T1, T2) :

This is equivalent to schedule-1.

Findings :

       Here, schedule-5 and schedule-1 are conflict equivalents.

          Here,  schedule-1 is a serial schedule.

       So,  schedule-5  is said to be conflict serializable.                          

       This concept is called ‘Conflict Serializability’.

Reference Links

Conflict Serializability