A department store runs a multiuser DBMS on a local area network file server whi
ID: 3684385 • Letter: A
Question
A department store runs a multiuser DBMS on a local area network file server which does not enforce concurrency control. One customer has a balance due of $250 when the following three transactions related to this customer were processed at the same time:
–Payment of $250
–Purchase on credit of $100
–Merchandise return of $50.
Each transaction reads the customer record when the balance was $250. the updated record was returned to the database in the order shown above.
•What balance will be for the customer after the last transaction was completed?
Explanation / Answer
300$