Example of Fund Transfer(Cont.) Isolation requirement-if between steps 3 and 6,another transaction is allowed to access the partially updated database,it will see an inconsistent database(the sum A B will be less than it should be). Isolation can be ensured trivially by running transactions serially, that is one after the other. However,executing multiple transactions concurrently has significant benefits,as we will see later. Durability requirement-once the user has been notified that the transaction has completed (i.e.,the transfer of the $50 has taken place),the updates to the database by the transaction must persist despite failures. Database System Concepts-5th Edition,Sep 10,2005. 15.6 ©Silberschat乜，Korth and SudarshanDatabase System Concepts - 5 15.6 ©Silberschatz, Korth and Sudarshan th Edition, Sep 10, 2005. Example of Fund Transfer (Cont.) Isolation requirement — if between steps 3 and 6, another transaction is allowed to access the partially updated database, it will see an inconsistent database (the sum A + B will be less than it should be). Isolation can be ensured trivially by running transactions serially, that is one after the other. However, executing multiple transactions concurrently has significant benefits, as we will see later. Durability requirement — once the user has been notified that the transaction has completed (i.e., the transfer of the $50 has taken place), the updates to the database by the transaction must persist despite failures