CS3319 Quizzes

Question 1

The speed and efficiency of the database is determined mainly at which level of the 3 Schema Architecture?

Accepted Answer

A. Internal Level

Answer

B. External Level

Answer

C. Conceptual Level

Question 2

Match the following attribute terminology to an example of each.

A. 250123456 (student number of a Western Student)
B. 65 Compton Cres, London, Ontario (street, city, prov)
C. 24 square metres (area of a rectangle where the width and height are also stored)
D. Phone Number (Cell, Home, Work)
E. Seat G4 (seat number given to a passenger taking a given flight)

[blank_start]1[blank_end]. Multivalued Attribute

[blank_start]2[blank_end]. Derived Attribute

[blank_start]3[blank_end]. Composite Attribute

[blank_start]4[blank_end]. Key Attribute

[blank_start]5[blank_end]. Relationship Attribute

Accepted Answer

D

Accepted Answer

C

Accepted Answer

B

Accepted Answer

A

Accepted Answer

E

Question 3

Assume we are designing an ER diagram for a restaurant, which of the following would be represented as an ENTITY? (Select all that apply)

Accepted Answer

Table

Accepted Answer

Waiter

Accepted Answer

Customer

Answer

Table Number (identifies the table within the restaurant)

Answer

Table Capacity (number of people who can sit at it)

Answer

Serves (e.g. Waiter servers Table)

Question 4

Multivalued attributes in an ER diagram will map to their own table in a relational database.

Answer

true

Question 5

Which of the following relationships has partial participation on the RIGHT side of the relationship (reading from left to right)?

Accepted Answer

ASTRONAUT lands on MOON

Answer

PLANET contains LIFE

Answer

PLANET orbited by MOON

Answer

SUN orbited by PLANET

Question 6

Which of the following entities on the RIGHT side of the relationship is NOT a weak entity?

Accepted Answer

TEACHER works at SCHOOL

Answer

BOOK has CHAPTER

Answer

BUILDING has ROOM

Answer

COURSE offers SECTION

Question 7

Match the term to an example of it (select the best pairing):

A. An art gallery with paintings, artists, employees, rooms, customers
B. Toronto
C. A Person's Calendar
D. MySQL or MSAccess

[blank_start]1[blank_end]. Data

[blank_start]2[blank_end]. Database

[blank_start]3[blank_end]. Mini-world

[blank_start]4[blank_end]. Database Management System (DBMS)

Accepted Answer

B

Accepted Answer

C

Accepted Answer

A

Accepted Answer

D

Question 8

Assuming students must work alone and they are taking an Writing course where essay writing is required, then the (min, max) participation on the LEFT side of the relationship:
STUDENT writes ESSAY
would likely be:
(1,1)

Answer

true

Question 9

Only one relationship can exist between two different entities.

Answer

true

Question 10

Match the following relationships to the correct cardinality.
A. MANY to MANY
B. ONE to ONE
C. ONE to MANY

[blank_start]1[blank_end]. CITY capital of COUNTRY

[blank_start]2[blank_end]. COUNTRY headed by (lead by) PRESIDENT

[blank_start]3[blank_end]. VOTER votes for CITY MAYOR CANDIDATE

[blank_start]4[blank_end]. MOON orbits PLANET

[blank_start]5[blank_end]. COUNTRY member of INTERNATIONAL_ORGANIZATION

[blank_start]6[blank_end]. COUNTRY borders COUNTRY

[blank_start]7[blank_end]. COUNTRY has PROVINCE

[blank_start]8[blank_end]. POLITICIAN speaks to REPORTER

Accepted Answer

B

Accepted Answer

B

Accepted Answer

C

Accepted Answer

C

Accepted Answer

A

Accepted Answer

A

Accepted Answer

C

Accepted Answer

A

Question 11

Given the following ER diagram, once it is completely mapped to a relational database, how many tables will be created?

Accepted Answer

4

Answer

1

Answer

2

Answer

3

Answer

5

Answer

6

Answer

More than 6 tables will be created.

Question 12

Given the following ER diagram, once it is completely mapped to a relational database, the STUDENT table and the PROFESSOR table will both have the exact same number of attributes?

Answer

true

Question 13

END OF QUIZ 1

Answer

true

Question 14

Why is a database normally stored on a Hard Disk rather than in Main Memory? Select all that apply

Accepted Answer

Because the hard disk is cheaper than main memory

Accepted Answer

Because the hard disk is less volatile than main memory

Accepted Answer

Because the hard disk can store more data than main memory

Answer

Because the hard disk has faster access than main memory

Answer

Because the hard disk takes up less physical space than main memory

Question 15

Which of the choices below would be considered good reasons for using a heap file organization? (Select ALL that apply)

Accepted Answer

Every time we use this table, we need to get every single tuple/record

Accepted Answer

This file (table/relation) is very small

Accepted Answer

The data will often be bulk loaded into the relation/table

Answer

Lots of searches will be required on the file

Answer

The data will have to be sorted often

Question 16

When adding the following values to a B+ tree with order 3 and pleaf=2, after adding all of the items below, what value will be in the root node? If 2 values will be in the root after all the values are added then select both values. You must go left down the tree for <= (less than or equal) and you must go right down the tree for > (greater than).

Values to be inserted into the B+ tree in THIS order:
8, 33, 44, 22, 10, 5, 4

Values to be inserted into the B+ tree in THIS order:
8, 33, 44, 22, 10, 5, 4

Accepted Answer

22

Accepted Answer

8

Answer

10

Answer

5

Answer

44

Answer

33

Answer

3

Question 17

Which of the following operations below will give us closure over strings? Check all that apply

Accepted Answer

Concatenate 2 strings - returns the 2 strings joined together

Accepted Answer

Trim a string (remove the spaces at the beginning and end of a string) - returns the trimmed string

Answer

Length of a string - returns the number of characters in a string

Answer

Position of one substring inside another - returns the position where one string is found inside another string. If the string is not found, then it returns -1

Question 18

How many rows will be returned from σd='B' (A)

Accepted Answer

3

Answer

1

Answer

2

Answer

4

Answer

None of the Above

Question 19

How many rows will be returned from πd (A)

Accepted Answer

2

Answer

1

Answer

3

Answer

None of the Above

Question 20

How many rows will be returned from πd (A) - πd (B)

Accepted Answer

1

Answer

0

Answer

2

Answer

3

Answer

None of the Above

Question 21

The will be [blank_start]__[blank_end] row(s) returned from (A ⋈ B)

Accepted Answer

6

Question 22

Assume we have the following two tables A and B

If we execute the relational algebra formula: (A  ⋈(aa=baa)  B)
Then the resulting table will contain [blank_start]__[blank_end] tuples and [blank_start]__[blank_end] attributes

Accepted Answer

2

Accepted Answer

5

Question 23

Given the following 2 tables: AA and BB:

The operation :
AA ∪ BB
Will produce how many tuples?

Accepted Answer

This operation cannot be done as these tables are not union compatible

Answer

Less than 4

Answer

4

Answer

5

Answer

More than 5

Question 24

Match the relational algebra query to what it represents in English.

A. (πFirstName (σCity='Toronto' (TEAM)  ⋈CaptainPlayerId=PlayerID  PLAYER))

B. (πFirstName (σCity='Toronto' (TEAM))  ⋈  PLAYER)

C. πTeamName (TEAM)

D. (πTeamName (σCity='Toronto' (TEAM)))

E. (πFirstName (TEAM  ⋈CaptainPlayerId=PlayerID  PLAYER))

[blank_start]1[blank_end]. Show me the team names of all the teams

[blank_start]2[blank_end]. Show me the first name of all players who play for a Toronto team

[blank_start]3[blank_end]. Show me the team name of all Toronto teams

[blank_start]4[blank_end]. Show me the first name of all team captains

[blank_start]5[blank_end]. Show me the first name of all the team captains for Toronto teams

Accepted Answer

C

Accepted Answer

B

Accepted Answer

D

Accepted Answer

E

Accepted Answer

A

Question 25

Look at tables A and B

Then the relation (Table AA joined with Table BB) is an example of what kind of join?

Accepted Answer

Left Outer Join

Answer

Natural Join

Answer

Full Outer Join

Answer

Right Outer Join

Question 26

END OF QUIZ 2

Answer

true

Question 27

How many rows would be returned from:
SELECT * FROM AA WHERE c = 7;

Accepted Answer

2

Answer

1

Answer

3

Answer

4

Answer

None of the above

Question 28

How many attributes would be returned from:
SELECT * FROM AA WHERE c = 7;

Accepted Answer

4

Answer

1

Answer

2

Answer

3

Answer

None of the above

Question 29

There would be [blank_start]__[blank_end] rows returned by this SQL statement:

SELECT b, c FROM AA WHERE d='B';

Accepted Answer

3

Question 30

There will be [blank_start]__[blank_end] rows returned by this SQL query:

SELECT a, f FROM AA, CC where b=e and d='B';

Accepted Answer

6

Question 31

This SQL command:

SELECT a, d FROM AA  WHERE c NOT IN (SELECT c FROM AA WHERE d="B");
will return [blank_start]__[blank_end] row(s).

Accepted Answer

1

Question 32

Decide if the following commands are either a MySQL command OR a standard SQL command

A. MySQL Command
B. SQL command

[blank_start]1[blank_end]. SHOW tables;

[blank_start]2[blank_end]. INSERT INTO customer (cid,first,last) VALUES ('100','Harry','Potter');

Accepted Answer

A

Accepted Answer

B

Question 33

Given tables AA and BB, the SQL command:

SELECT a, AA.b, f FROM AA, BB WHERE c=5;

will return [blank_start]__[blank_end] columns and [blank_start]__[blank_end] rows.

Accepted Answer

3

Accepted Answer

6

Question 34

How many rows would be returned from:

SELECT SUM(a) FROM A GROUP BY c;
assuming you have the following tables:

Accepted Answer

C. 2

Answer

A. less than 1

Answer

B. 1

Answer

D. 3

Answer

E. 4

Answer

F. more than 4

Question 35

An instance of an entity of type A could be further classified as an entity of type B AND as an entity of type C at the same time.

Answer

true

Question 36

Given the following diagram and assuming you are going to store information about all Canadian animals and no additional entities will be added, what type of line should the red line be?

Accepted Answer

Single

Answer

Dashed

Answer

Double

Question 37

Given these tables, the following relational calculus expression will return [blank_start]__[blank_end] tuples/rows and [blank_start]__[blank_end] attributes.
{t | B(t) AND t.baa = "a4"}

Accepted Answer

3

Accepted Answer

2

Question 38

Given the tables below, how many tuples would the following relational calculus return?

{a.aa, a.bb | A(a) and (( ∃b)(B(b) and b.baa=a.aa and a.cc>3}

Accepted Answer

B. 2

Answer

A. Less than 2

Answer

C. 3

Answer

D. 4

Answer

E. 5

Answer

F. 6

Answer

G. 7

Answer

H. 8

Answer

I. More than 8

Question 39

Assume you have created a table called bloodtype using this command:

CREATE TABLE bloodtype (bloodtypeid CHAR(2), rhfactor CHAR(1), type CHAR(2), percent INT, PRIMARY KEY (bloodtypeid));

The SQL command to add the row for the blood type of AB positive (+) where 17% of the population have that type would be:

[blank_start]_______[blank_end] INTO bloodtype VALUES ('08','+','AB',17);

Accepted Answer

INSERT

Question 40

END OF QUIZ 3

Answer

true

Question 41

$EmpName and $empname are different variables in PHP.

Answer

true

Question 42

PHP server scripts (PHP code) are surrounded by delimiters, what are they?

Accepted Answer

A. <?php...?>

Answer

B. <?php>...</?>

Answer

C. <script>...</script>

Answer

D. <&>...</&>

Question 43

All PHP code runs on the server, never on the client machine.

Answer

true

Question 44

In PHP you can use both single quotes ( ' ' ) and double quotes ( " " ) for strings.

Answer

true

Question 45

What PHP code will send "Hello World" to be displayed on a webpage?

Accepted Answer

B. echo "Hello World";

Answer

A. Document.Write("Hello World");

Answer

C. System.out("Hello World");

Question 46

Match the following PHP to the task it performs.

A. Performs a query on the database
B. Opens a connection to a database
C. Returns one row from a retreived query
D. Closes a connection to a database

[blank_start]1[blank_end]. mysqli_connect($dbhost,$dbuser,$dbpass,$dbname);

[blank_start]2[blank_end]. mysqli_fetch_assoc($result)

[blank_start]3[blank_end]. mysqli_query($connection,$query)

[blank_start]4[blank_end]. mysqli_close($connection);

Accepted Answer

B

Accepted Answer

C

Accepted Answer

A

Accepted Answer

D

Question 47

Given the 2 tables: pet and owner with the following data:

And the following php code (assume the connection was made to the database):

What would be outputted by the code above?

Accepted Answer

1. dog
2. Brian
3. Brian

Answer

1. dog
2. Waffles
3. Chimo

Answer

1. dog
2. Brian
3. Chimo

Answer

1. dog
2. Waffles
3. Waffles

Answer

None of the above

Question 48

Assume we have tables AA (integer columns a, b and c) and BB (integer column e and d - table is empty initially) as shown below and we have the MySQL trigger shown below.

After we execute the following two SQL statements:
INSERT INTO BB (e, d) VALUES (20,10);
SELECT * FROM AA ORDER BY c;

then the values for the FIRST displayed row of table AA will be:
a will have the value of [blank_start]__[blank_end] 
b will have the value of [blank_start]__[blank_end]
c will have the value of [blank_start]__[blank_end]

Accepted Answer

10

Accepted Answer

30

Accepted Answer

3

Question 49

Assume we are drawing an ER diagram of the entities in a relational database, match the entity name to what it would become in the ER diagram

A. Weak Entity
B. Attribute - Primary Key
C. Attribute - Weak Key
D. Entity
E. Derived Attribute

[blank_start]1[blank_end]. Table

[blank_start]2[blank_end]. Column

[blank_start]3[blank_end]. Database

[blank_start]4[blank_end]. DatabaseName

[blank_start]5[blank_end]. TableName

[blank_start]6[blank_end]. NumOfRowsInTable

Accepted Answer

A

Accepted Answer

A

Accepted Answer

D

Accepted Answer

B

Accepted Answer

C

Accepted Answer

E

Question 50

Assume I perform the following SQL commands:

If I compare the count returned from Line 1 to the count returned in Line 4, the count value would have changed by [blank_start]__[blank_end].

If I compare the count returned by Line 2 to the count returned by Line 5, the count value would have changed by [blank_start]__[blank_end].

If I compare the count returned by Line 3 to the count returned by Line 6, the count value would have changed by [blank_start]__[blank_end].

Accepted Answer

1

Accepted Answer

1

Accepted Answer

1

Question 51

Which of the following is NOT a method for handling leaks of information via Statistical Database Queries

Accepted Answer

C. Restrict user from using aggregate functions such as AVERAGE,COUNT, MIN, MAX, ete. Only let them do SELECT * FROM ... type of queries.

Answer

A. Limit queries if the result returns a number of rows less than a certain threshold of rows

Answer

B. Limit repeated queries that refer to the same tuples

Answer

D. Introduce "noise" (inaccuracies) into results to make it difficult to deduce individual information

Answer

E. All of the above are methods used to stop leaks in Statistical Database Security.

Question 52

Role Based Security is useful (select all that apply)

Accepted Answer

If you have a company with thousands of employees

Accepted Answer

If groups of employees in your company have predefined roles and each role should have the same level of access (select or insert or etc..) to the tables/databases/columns.

Answer

If you need to do statistical queries that use aggregate functions such as MAX, MIN, COUNT and AVG.

Answer

if you want to give people and the data top secret, secret, confidential and unclassified levels of control.

Question 53

END OF QUIZ 4

Answer

true

Question 54

Assume you have the following table: R with attributes: {A, B, C, D, E, F, G, H, I, J, K} and the following dependencies: { (B, D, G --> C, E), (B, D --> K), (B-->A, F), (G-->H), {H-->I}, {I-->J}}

How many tables, in total, will there be when you put R into second normal form?

Accepted Answer

D. 4

Answer

A. 1

Answer

B. 2

Answer

C. 3

Answer

E. More than 4

Question 55

Assume you have the following table: R with attributes: {A, B, C, D, E, F, G, H, I, J, K} and the following dependencies: { (B, D, G --> C, E), (B, D --> K), (B-->A, F), (G-->H), {H-->I}, {I-->J}}

How many tables, in total, will there be when you put R into third normal form?

Accepted Answer

D. 6

Answer

A. 3

Answer

B. 4

Answer

C. 5

Answer

E. more than 6

Question 56

Assume you have the following table: R with attributes: {A, B, C, D, E, F, G, H, I, J, K} and the following dependencies: { (B, D, G --> C, E), (B, D --> K), (B-->A, F), (G-->H), {H-->I}, {I-->J}}

K is partially functionally dependent on B, D?

Answer

true

Question 57

LicencePlateNumber --> CarColour

Answer

true

Question 58

Which of the following granualarities of locking will be the least restrictive to other transactions that are waiting for a locked item?

Accepted Answer

Field Level

Answer

Which of the following granualarities of locking will be the least restrictive to other transactions that are waiting for a locked item?

Answer

Table Level

Answer

RowLevel

Answer

Page Level

Question 59

Assume we have two transactions T1 and T2. We could have a schedule S1 which performs all of T1 then all of T2. Or we could have another schedule S2, which performs all of T2 then all of T1. If S1 results in different values in the database than S2 would have given, S1 and/or S2 did NOT represent serializable schedules.

Answer

true

Question 60

Assume you create a transaction called T1 that requests the average of the prices for all the items in your warehouse. After T1 has started running, T2 starts running to increase all the item prices by 5%. Thus, your final average represents the average of some prices with the old value and some with the new value. This type of transaction corruption is referred to as:

Accepted Answer

Inconsistent Retrieval

Answer

A Lost Update

Answer

Uncommitted Data

Answer

It is okay for a transaction to allow this to happen, as long as it is only reading the data and reporting the results without updating the data (Thus, transaction T1 is not a problem)

Question 61

Assuming you have three transactions: T1, T2 and T3.
Then, the number of possible serial schedules that exist is:  [blank_start]__[blank_end]

Accepted Answer

6

Question 62

Assume we have a sparse index on the Price attribute in a Products table. Which of the following SQL statements would be speed up the query AND give the correct results by ONLY referencing the index file (and never touching the actual product table). Check all that apply.

Accepted Answer

SELECT MIN(price) FROM product;

Accepted Answer

SELECT MAX(price) FROM product;

Answer

SELECT AVERAGE(price) FROM product;

Answer

SELECT SUM(price) FROM product;

Answer

SELECT COUNT(price) FROM product;

Question 63

The following table is not normalized:

Answer

true

Question 64

When using Time Stamping, which of the following Time Stamps do you need to save in a situation where Transaction T is trying to use the piece of data called Quantity? (Select all that apply)

Accepted Answer

Start Time of Transaction T

Accepted Answer

Read Time of (Quantity)

Accepted Answer

Write Time of (Quantity)

Answer

End Time of Transaction T

CS3319 Quizzes

Preguntas del test (66)

Información

Escríbenos

¿Qué te parece el nuevo diseño?