Which of the following ACID property in DBMS ensures that the concurrent execution of transactions results in a system state that would be obtained if transactions were executed serially, i.e. one after the other?
Correct Answer: C
Explanation/Reference: Isolation - The isolation property ensures that the concurrent execution of transactions results in a system state that would be obtained if transactions were executed serially, i.e. one after the other. For CISA exam you should know below information about ACID properties in DBMS: Atomicity - Atomicity requires that each transaction is "all or nothing": if one part of the transaction fails, the entire transaction fails, and the database state is left unchanged. An atomic system must guarantee atomicity in each and every situation, including power failures, errors, and crashes. To the outside world, a committed transaction appears (by its effects on the database) to be indivisible ("atomic"), and an aborted transaction does not happen. Consistency - The consistency property ensures that any transaction will bring the database from one valid state to another. Any data written to the database must be valid according to all defined rules, including but not limited to constraints, cascades, triggers, and any combination thereof. This does not guarantee correctness of the transaction in all ways the application programmer might have wanted (that is the responsibility of application-level code) but merely that any programming errors do not violate any defined rules. Isolation - The isolation property ensures that the concurrent execution of transactions results in a system state that would be obtained if transactions were executed serially, i.e. one after the other. Providing isolation is the main goal of concurrency control. Depending on concurrency control method, the effects of an incomplete transaction might not even be visible to another transaction. [citation needed] Durability - Durability means that once a transaction has been committed, it will remain so, even in the event of power loss, crashes, or errors. In a relational database, for instance, once a group of SQL statements execute, the results need to be stored permanently (even if the database crashes immediately thereafter). To defend against power loss, transactions (or their effects) must be recorded in a non-volatile memory. The following were incorrect answers: Consistency - The consistency property ensures that any transaction will bring the database from one valid state to another. Any data written to the database must be valid according to all defined rules, including but not limited to constraints, cascades, triggers, and any combination thereof. This does not guarantee correctness of the transaction in all ways the application programmer might have wanted (that is the responsibility of application-level code) but merely that any programming errors do not violate any defined rules. Durability - Durability means that once a transaction has been committed, it will remain so, even in the event of power loss, crashes, or errors. Atomicity requires that each transaction is "all or nothing": if one part of the transaction fails, the entire transaction fails, and the database state is left unchanged. The following reference(s) were/was used to create this question: CISA review manual 2014 Page number 218
Question 152
Responsibility and reporting lines cannot always be established when auditing automated systems since:
Correct Answer: C
Explanation/Reference: Explanation: Because of the diversified nature of both data and application systems, the actual owner of data and applications may be hard to establish.
Question 153
.Library control software restricts source code to:
Correct Answer: A
Library control software restricts source code to read-only access.
Question 154
A characteristic of a digital signature is that it:
Correct Answer: B
Question 155
What is used to develop strategically important systems faster, reduce development costs, and still maintain high quality?
Correct Answer: A
Explanation/Reference: Explanation: Rapid application development (RAD) is used to develop strategically important systems faster, reduce development costs, and still maintain high quality.
