That consistent state cannot be lost, even in the event of a system’s failure. When a transaction is completed, then the database reaches a state known as the consistent state. They cannot be lost by the erroneous operation of a faulty transaction or by the system failure.It states that the transaction made the permanent changes. The durability property is used to indicate the performance of the database’s consistent state.The concurrency control subsystem of the DBMS enforced the isolation property.In isolation, if the transaction T1 is being executed and using the data item X, then that data item can’t be accessed by any other transaction T2 until the transaction T1ends.It shows that the data which is used at the time of execution of a transaction cannot be used by the second transaction until the first one is completed.The transaction is used to transform the database from one consistent state to another consistent state.The consistent property of database states that every transaction sees a consistent database instance.The execution of a transaction will leave a database in either its prior stable state or anew stable state.The integrity constraints are maintained so that the database is consistent before and after the transaction.Commit : If a transaction commits then all the changes made are visible.Abort: If a transaction aborts, then all the changes made are not visible.
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