Question 1

In the optimistic approach, during the phase, a transaction scans the database, executes the needed computations, and makes the updates to a private copy of the database values.

Accepted Answer

A)  read 
B)  validation 
C)  write 
D)  shared

Question 2

The interleaves the execution of database operations to ensure serializability.

Accepted Answer

The answer of The interleaves the execution of database operations...

Question 3

If T1 has not unlocked data item Y, T2 cannot begin; if T2 has not unlocked data item X, T1 cannot continue. Consequently, T1 and T2 each wait for the other to unlock the required data item. Such a deadlock is also known as a(n) _____.

Accepted Answer

The answer of If T1 has not unlocked data item...

Question 4

Most multiuser automatically initiate and enforce locking procedures, where all locking information is managed by the lock manager.

Accepted Answer

The answer of Most multiuser automatically initiate and enforce locking...

Question 5

control is important because the simultaneous execution of transactions over a shared database can create several data integrity and consistency problems.

Accepted Answer

The answer of control is important because the simultaneous execution...

Question 6

-level locks are less restrictive than database-level locks, but they create traffic jams when many transactions are waiting to access the same table.

Accepted Answer

The answer of -level locks are less restrictive than database-level...

Question 7

Most real-world database transactions are formed by only one database request.

Accepted Answer

A) True 
 B)False

Question 8

A growing phase in a two-phase lock is when a transaction acquires all the required locks without locking any data.

Accepted Answer

A) True 
 B)False

Question 9

In the optimistic approach, during the phase, changes are permanently applied to the database.

Accepted Answer

A)  read 
B)  validation 
C)  write 
D)  shared

Question 10

occurs when a transaction accesses data before and after one or more other transactions finish working with such data.

Accepted Answer

A)  Inconsistent retrievals 
B)  The phenomena of uncommitted data 
C)  Lost update problems 
D)  Dirty read problems

Question 11

A shared lock produces no conflict as long as all the concurrent transactions are read-write only.

Accepted Answer

A) True 
 B)False

Question 12

Incomplete or improper transactions can have a devastating effect on database integrity.

Accepted Answer

A) True 
 B)False

Question 13

A(n) lock exists when concurrent transactions are granted read access on the basis of a common lock.

Accepted Answer

A)  shared 
B)  exclusive 
C)  binary 
D)  two-phase

Question 14

A(n) condition occurs when two or more transactions wait for each other to unlock data.

Accepted Answer

A)  deadlock 
B)  exclusive lock 
C)  binary lock 
D)  two-phase lock

Question 15

A occurs when two or more transactions wait for each other to unlock data.

Accepted Answer

A)  livelock 
B)  database deadlock 
C)  distributed deadlock 
D)  phantom deadlocks

Question 16

The multiuser DBMS must implement controls to ensure serializability and isolation of transactions, in addition to atomicity and durability, in order to guard the database's consistency and integrity.

Accepted Answer

A) True 
 B)False

Question 17

can take place at any of the following levels: database, table, page, row, or field.

Accepted Answer

The answer of can take place at any of the...

Question 18

The occurs when two concurrent transactions, T1 and T2, are updating the same data element and one of the updates is lost.

Accepted Answer

The answer of The occurs when two concurrent transactions, T1...

Question 19

The serializable isolation level is the least restrictive level defined by the ANSI SQL standard.

Accepted Answer

A) True 
 B)False

Question 20

What are the three basic techniques to control deadlocks?

Accepted Answer

The answer of What are the three basic techniques to...

Exam 10: Transaction Management and Concurrency Control

In the optimistic approach, during the phase, a transaction scans the database, executes the needed computations, and makes the updates to a private copy of the database values.

The interleaves the execution of database operations to ensure serializability.

If T1 has not unlocked data item Y, T2 cannot begin; if T2 has not unlocked data item X, T1 cannot continue. Consequently, T1 and T2 each wait for the other to unlock the required data item. Such a deadlock is also known as a(n) _____.

Most multiuser automatically initiate and enforce locking procedures, where all locking information is managed by the lock manager.

control is important because the simultaneous execution of transactions over a shared database can create several data integrity and consistency problems.

-level locks are less restrictive than database-level locks, but they create traffic jams when many transactions are waiting to access the same table.

Most real-world database transactions are formed by only one database request.

A growing phase in a two-phase lock is when a transaction acquires all the required locks without locking any data.

In the optimistic approach, during the phase, changes are permanently applied to the database.

occurs when a transaction accesses data before and after one or more other transactions finish working with such data.

A shared lock produces no conflict as long as all the concurrent transactions are read-write only.

Incomplete or improper transactions can have a devastating effect on database integrity.

A(n) lock exists when concurrent transactions are granted read access on the basis of a common lock.

A(n) condition occurs when two or more transactions wait for each other to unlock data.

A occurs when two or more transactions wait for each other to unlock data.

The multiuser DBMS must implement controls to ensure serializability and isolation of transactions, in addition to atomicity and durability, in order to guard the database's consistency and integrity.

can take place at any of the following levels: database, table, page, row, or field.

The occurs when two concurrent transactions, T1 and T2, are updating the same data element and one of the updates is lost.

The serializable isolation level is the least restrictive level defined by the ANSI SQL standard.

What are the three basic techniques to control deadlocks?