Review Questions

Question 1

Is this schedule
w1(x) r1(x) w3(z) cl r2(x) r2() r4(E) c4 c2 r3(x) w3 (V) c3
strict?
(NOTE: Schedule in which a Transaction can neither read or write an item X until the last Transaction that wrote X has Committed.)

Answer 1

No

Question 2

During the undo phase, the recovery system writes compensation records for:

Answer 2

Transactions that do not commit or roll back following the most recent checkpoint

Question 3

A ______ statement temporarily saves data read and written by a transaction

Answer 3

SAVEPOINT

Question 4

The transaction is always durable

Answer 4

False

Question 5

AHow many SQL statements must be in one transaction?

Answer 5

At least one

Question 6

Which of the following is NOT true of the two phase locking protocol

Answer 6

It eliminates the problem of deadlock

Question 7

Would T2 get a shared lock

Answer 7

Yes

Question 8

Select Transaction 5 Isolation level

Answer 8

READ UNCOMMITTED

Question 9

Select the correct option for the following:
Transaction 1

Answer 9

SERIALIZABLE

Question 10

The _____ Schedule has a different result than schedule

Answer 10

Conflicting

Question 11

Which two phase locking technique has, in effect, just one phase?

Answer 11

Rigorous

Question 12

SERIALIZABLE transaction can run concurrently with a READ COMMITTED transaction

Answer 12

TRUE

Question 13

When a transaction deletes a table row, an ______ record is written in the log

Answer 13

update

Question 14

Consider the following sequence of actions, listed in the order they are submitted to the DBMS: w1(x) r2(x) w2(v) w2(x) w3(z) r3(v) w3(v) wl(z) abortl
Does deadlock exists?

Answer 14

Yes

Question 15

A transaction updates an account with a foreign key. The FK does not match any values of the corresponding PK and is not null

Answer 15

Consistent

Question 16

Trans A writes data and rolls back before transaction B reads data

Answer 16

Strict

Question 17

The privelage list of the SQL GRANT statement may include all of the following except

Answer 17

REPLACE

Question 18

Transactions A and B are both serializable and A always starts before B, the results may vary

Answer 18

False

Question 19

Several transactions can hold concurrent exclusive locks on the same row

Answer 19

False

Question 20

In recovery techniques, ______ requires that the effects of a committed transaction be permenant so they must survive a loss of main memory, loss of disk storage etc

Answer 20

Durability

Question 21

Grant _____ ON DEPTINFOR To assistant

Answer 21

SELECT

Question 22

During the undo phase, the recovery system reads the log in reverse and stops at

Answer 22

The start record for the last transaction in the active transaction list

Question 23

After a rollback the database restarts a transaction

Answer 23

Sometimes

Question 24

Select Transaction 5 transaction boundry

Answer 24

Start and End

Question 25

A document that sequentially writes all the database operations known as an

Answer 25

Recovery Log

Question 26

In which isolation level can dirty reads occur

Answer 26

Read Uncommitted

Question 27

When using the MySQL Workbench the _________ ison will execute an SQL statement

Answer 27

Lightning Bolt

Question 28

Which MySQL component retains data blocks from storage in main memory for possible resuse

Answer 28

Buffer Manager

Question 29

In the recovery log below line 6 is an

Answer 29

Compensation Record

Question 30

A transaction ________ indicates the staring and ending statement of a DB transaction

Answer 30

Boundry

Question 31

Which isolation level prevents dirty non repeatable and phantom reads

Answer 31

Serializable