Deck 2: The Relational Model 1: Introduction, QBE, and Relational Algebra

Question 1

A relational database handles entities, attributes, and relationships by storing each entity in its own row.

Answer 1

False

Question 2

In an AND criterion, the overall criterion is true if either of the individual criteria is true.

Answer 2

False

Question 3

The concept of grouping means that statistics will be calculated for individual records.

Answer 3

False

Question 4

In the Access Query window, the upper portion of the window contains the design grid.

Question 5

A relational database is a collection of tables.

Question 6

The primary key of a table is the row or rows that uniquely identify a given column in that table.

Question 7

In relational database shorthand, the structure of a relational database is written with the name of the table followed by the columns in the table listed within parentheses.

Question 8

The field on which records are sorted is called the composite primary key.

Question 9

A column whose value uniquely identifies a given row in the table is the secondary key.

Question 10

The relational operators are +, *, %, and /.

Question 11

To select data from more than one table at the same time, you need to perform a make-table query.

Question 12

Which term is another word for a row in a table?

A) tuple
B) field
C) group
D) relation

Question 13

What uniquely identifies a row in a table?

A) attribute
B) column
C) primary key
D) field

Question 14

The attributes of an entity become the fields or columns in a table.

Question 15

Which of the following is NOT true about a relation in a two-dimensional table?

A) The entries in the table are single-valued.
B) All values in a column are values of the same attribute.
C) Two or more columns can share the same name.
D) The order of rows is immaterial.

Question 16

How do you refer to a column named State in a table named Client?

A) State.Client
B) State(Client)
C) Client.State
D) Client(State)

Question 17

In Access, a parameter query allows you to enter criterion when you run the query.

Question 18

In a relation, the order of rows is important.

Question 19

Which of the following is the column or collection of columns that uniquely identifies a given row in that table?

A) primary key
B) secondary key
C) foreign key
D) minor key

Question 20

A query is a question represented in a way that the DBMS can recognize and process.

Question 21

Which command creates a table containing all rows that are in either or both of two tables?

A) UNION
B) SUBTRACT
C) JOIN
D) INTERSECT

Question 22

Which operation is performed by the SUBTRACT command in relational algebra?

A) union
B) difference
C) product
D) intersection

Question 23

The relationships between tables are implemented through common ____________________.

Question 24

Which command contains all rows that are common in two tables?

A) UNION
B) SUBTRACT
C) JOIN
D) INTERSECT

Question 25

The compound criteria (conditions) are created by using which of the following two keywords?

A) AND, OR
B) AND, NOR
C) OR, NOT
D) NOT, ONLY

Question 26

A(n) ____________________ database is a collection of tables.

Question 27

Based on the table below, which command creates a new table named CustState containing the fields CustomerNum and State??Customer (CustomerNum, CustomerName, Street, City, State, PostalCode)

A) JOIN Customer WITH (CustomerNum, State) GIVING CustState
B) PROJECT Customer OVER (CustomerNum, State) GIVING CustState
C) SELECT Customer OVER (CustomerNum, State) GIVING CustState
D) MAKE-TABLE CustState FROM Customer WITH (CustomerNum, State)

Question 28

Which operation will allow you to extract data from more than one table?

A) Select
B) Merge
C) Project
D) Join

Question 29

Based on the tables below, which command creates a new table named CustSales that combines the Customer and SalesPerson tables based on SalesPersonNum??Customer (CustomerNum, CustomerName, Street, City, State, PostalCode, SalesPersonNum)?SalesPerson (SalesPersonNum, LastName, FirstName)

A) PROJECT Customer SalesPerson WHERE Customer.SalesPersonNum=SalesPerson.SalesPersonNum MAKING CustSales
B) UNION Customer SalesPerson WHERE Customer.SalesPersonNum=SalesPerson.SalesPersonNum MAKING CustSales
C) SELECT Customer SalesPerson JOIN Customer.SalesPersonNum=SalesPerson.SalesPersonNum GIVING CustSales
D) JOIN Customer SalesPerson WHERE Customer.SalesPersonNum=SalesPerson.SalesPersonNum GIVING CustSales

Question 30

Multiple entries in tables are often called ____________________.

Question 31

When some of the entries in a structure contain repeating groups and thus are not single-valued, the structure is called a(n) ____________________.

Question 32

Which of the following is true if two tables have the same number of columns and their corresponding columns represent the same type of data?

A) They are union compatible.
B) They are intersection compatible.
C) They are difference compatible.
D) They are product compatible.

Question 33

In relational algebra, what command causes only certain columns to be included in the new table?

A) SELECT
B) DELETE
C) PROGRAM
D) PROJECT

Question 34

Which operator is used to concatenate every row in the first table with every row in the second table?

A) union
B) difference
C) product
D) intersection

Question 35

What type of query changes data?

A) addition
B) update
C) update
D) select

Question 36

A ______________ primary key is composed of more than one column so that the row is unique.

Question 37

Based on the table below, which command lists all information from the table concerning the customer with CustomerNum 260? Customer (CustomerNum, CustomerName, Street, City, State, PostalCode)

A) SELECT Customer 260 RESULTS Answer
B) SELECT Customer WHERE CustomerNum=260 GIVING Answer
C) SELECT Customer GIVING Answer WHERE CustomerNum='260'
D) SELECT Customer WHERE CustomerNum='260' RESULTS Answer

Question 38

If you are sorting records by more than one field, which field is the more important field?

A) primary sort key
B) secondary sort key
C) maximum sort key
D) minor sort key

Question 39

What type of query creates a new table using the query results?

A) new-table
B) make-table
C) create-table
D) merge-table

Question 40

What type of functions are Count, Sum, Avg, Max, and Min?

A) accumulation
B) allowed
C) primary
D) aggregate

Question 41

Discuss the difference between the major sort key and the minor sort key.

Question 42

A(n) ______________ query makes a specified change to all records satisfying the criteria in the query.

Question 43

List the six properties that define a relation in a two-dimensional table.

Question 44

What is the difference between an AND criterion and an OR criterion?

Question 45

List at least six of the aggregate functions available in Access.

Question 46

To list the records in a query's results in a particular order, you need to ____________________ the records.

Question 47

When both criteria must be true for the compound criterion to be true, the _______________ operator is being used.

Question 48

Explain what relational algebra is and how it is used.

Question 49

A query ___________________ is a DBMS component that analyzes queries and attempts to determine the most efficient way to execute a given query.

Question 50

A ____________________ query in Access allows you to enter criterion when you run the query, as opposed to placing it in the design grid.