CSE 511 Week 3 UPDATED ACTUAL
Exam Questions and CORRECT Answers
What is the result of the following database transaction if the initial values of both A and B is
100?
BEGIN
A = A + 100
B = A + 100 - CORRECT ANSWER -A = 200
B = 300
How does a database achieve concurrency? - CORRECT ANSWER -A DB can process
multiple transactions concurrently by interleaving them
What describes the atomicity principle of database transactions? - CORRECT ANSWER -
All of the components of a transaction run in their entirety, all of them or none of them run at all
What kind of lock must a transaction acquire in order to read from a DB? - CORRECT
ANSWER -Shared Lock
What kind of DB operation does NOT require a transaction to obtain an exclusive lock? -
CORRECT ANSWER -Read Data
Why do DBMSs implement transaction interleaving? - CORRECT ANSWER -To achieve
concurrency
What describes the isolation principle of database transactions? - CORRECT ANSWER -
Each transaction runs as if there is no other transaction running in the DB system simultaneously
Exam Questions and CORRECT Answers
What is the result of the following database transaction if the initial values of both A and B is
100?
BEGIN
A = A + 100
B = A + 100 - CORRECT ANSWER -A = 200
B = 300
How does a database achieve concurrency? - CORRECT ANSWER -A DB can process
multiple transactions concurrently by interleaving them
What describes the atomicity principle of database transactions? - CORRECT ANSWER -
All of the components of a transaction run in their entirety, all of them or none of them run at all
What kind of lock must a transaction acquire in order to read from a DB? - CORRECT
ANSWER -Shared Lock
What kind of DB operation does NOT require a transaction to obtain an exclusive lock? -
CORRECT ANSWER -Read Data
Why do DBMSs implement transaction interleaving? - CORRECT ANSWER -To achieve
concurrency
What describes the isolation principle of database transactions? - CORRECT ANSWER -
Each transaction runs as if there is no other transaction running in the DB system simultaneously
