Question 1

An ER diagram that contains two entities involved in two separate M:N relationships will be mapped as how many relations?
A)1
B)2
C)3
D)4

Accepted Answer

Each M:N relationship is mapped to a separate relation, and each entity is also mapped to a relation. Therefore, two entities and two M:N relationships result in four relations.

Question 2

If an M:N relationship is optional on both sides,and if both relations resulting from the entities involved in the relationship each have 3 records,then the resulting bridge relation cannot have less than ________ records.
A)0
B)1
C)3
D)9

Accepted Answer

Since the relationship is optional on both sides, it's possible that none of the entities are related to each other, resulting in 0 records in the bridge relation.

Question 3

An entity with two multivalued attributes will be mapped as how many relations?
A)1
B)2
C)3
D)4

Accepted Answer

An entity with two multivalued attributes will be mapped as 3 relations: 
1. A relation for the entity itself 
2. A relation for one multivalued attribute and primary key of the entity 
3. Another relation for the other multivalued attribute and primary key of the entity

Question 4

Which of the following is NOT true? Mapping an M:N relationship that has no attributes will result in:
A)A new relation
B)Two foreign keys
C)A composite primary key
D)A foreign key in both of the relations mapped from the involved entities

Accepted Answer

In an M:N relationship without attributes, a new relation is created to map the relationship, which includes two foreign keys (one from each of the entities involved in the relationship) and often uses these foreign keys together as a composite primary key. However, it does not result in a foreign key being placed in both of the original entity relations; instead, the foreign keys are part of the new relation created to represent the M:N relationship.

Question 5

If an M:N relationship is mandatory on both sides,and if both relations resulting from the entities involved in the relationship each have 3 records,then the resulting bridge relation cannot have less than ________ records.
A)0
B)1
C)3
D)9

Accepted Answer

If an M:N relationship is mandatory on both sides, then each entity in the relationship must be related to at least one other entity. If both relations resulting from the entities involved in the relationship each have 3 records, then there must be at least 3 records in the resulting bridge relation.

Question 6

If a 1:M relationship is mandatory on the M side and optional on the 1 side,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side cannot have less than ________ records.
A)0
B)1
C)2
D)3

Accepted Answer

Since the relationship is mandatory on the M side, every record in the M side table must be associated with a record in the 1 side table. However, since it's optional on the 1 side, not every record on the 1 side needs to have a corresponding record on the M side. Given there are 3 records on the 1 side, the minimum number of records on the M side to satisfy the mandatory relationship is 3, one for each record on the 1 side.

Question 7

If a 1:M relationship is mandatory on both sides,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side CANNOT have less than ________ records.
A)0
B)1
C)2
D)3

Accepted Answer

Since the relationship is mandatory on both sides, each record on the 1 side must be associated with at least one record on the M side, and there cannot be any record on the M side without a corresponding record on the 1 side. Therefore, with 3 records on the 1 side, there must be at least 3 records on the M side to satisfy the mandatory relationship.

Question 8

If a 1:M relationship is mandatory on both sides,which of the following is true?
A)The resulting foreign key can have null (empty)values
B)The resulting foreign key cannot have null (empty)values
C)The resulting foreign key must have null (empty)values
D)No foreign key is created as a result of mapping such a relationship

Accepted Answer

If the 1:M relationship is mandatory on both sides, then the resulting foreign key cannot have null (empty) values. This ensures that every record in the child table has a corresponding record in the parent table, and vice versa, with no missing or orphaned records.

Question 9

If a 1:M relationship is optional on the M side and mandatory on the 1 side,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side CANNOT have less than ________ records.
A)0
B)1
C)2
D)3

Accepted Answer

The answer of If a 1:M relationship is optional on...

Question 10

If a 1:M relationship is optional on both sides,which of the following is true?
A)The resulting foreign key can have null (empty)values
B)The resulting foreign key cannot have null (empty)values
C)The resulting foreign key must have null (empty)values
D)No foreign key is created as a result of mapping such a relationship

Accepted Answer

If a 1:M relationship is optional on both sides, then it means that one record in the '1' table can be related to multiple records in the 'M' table, but it doesn't have to be mandatory to have a match. Similarly, a record in the 'M' table can be related to only one record in the '1' table or none at all. In this scenario, the resulting foreign key in the 'M' table can have null values because not every record in the 'M' table needs to have a match in the '1' table. Therefore, option A is correct.

Question 11

Which of the following statements regarding the table below is true?
$$\begin{array} { | l | l | l |} 
 \hline \text { ColumnA } & \text { ColumnB } & \text { ColumnC } \
\hline
\end{array}$$
A)Every value in Column A is unique
B)Every value in Column B is unique
C)Every combination of values in Column A and Column B within the same row is unique
D)All of the above

Accepted Answer

Option A and Option B statements cannot be determined from the given table as there are no values in it. However, Option C is clearly true as each row has unique combinations of Column A and Column B values. Therefore, only Option C is the correct choice.

Question 12

If an entity has three unique attributes,how many primary keys will its mapped relation have?
A)0
B)1
C)2
D)3

Accepted Answer

A primary key is a unique identifier for each record in a relation. Since the entity has three unique attributes, it is possible to have one of these attributes as the primary key for the mapped relation. Therefore, the mapped relation will have one primary key.

Question 13

Which of the following is NOT true? In a relational database:
A)Two tables can be a part of the same database
B)Two tables can have the same number of columns
C)Two tables can have the same number of rows
D)Two tables can have the same names

Accepted Answer

In a relational database, two tables cannot have the same name as each table must have a unique identifier.

Question 14

If a 1:M relationship is optional on both sides,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side CANNOT have less than ________ records.
A)0
B)1
C)2
D)3

Accepted Answer

Since the relationship is optional on both sides, the table on the M side can have 0 records, as there is no requirement for a minimum number of connections.

Question 15

If a 1:M relationship is mandatory on the 1 side and optional on the M side,which of the following is true?
A)The resulting foreign key can have null (empty)values
B)The resulting foreign key cannot have null (empty)values
C)The resulting foreign key must have null (empty)values
D)No foreign key is created as a result of mapping such a relationship

Accepted Answer

In a mandatory 1:M relationship, every record in the 1 table must have at least one related record in the M table. However, in the M table, some records may not have a related record in the 1 table. Therefore, the foreign key in the M table cannot be null as every record needs to have a reference to the 1 table.

Question 16

Relation is a synonym for
A)Column
B)Field
C)Row
D)Table

Accepted Answer

In database terminology, a relation is synonymous with a table, which is a structured set of data made up of rows and columns.

Question 17

Tuple is a synonym for
A)Column
B)Field
C)Row
D)Table

Accepted Answer

A tuple is a synonym for a row in a database table, representing a single record.

Question 18

If an M:N relationship is mandatory on one side and optional on the other side,and if both relations resulting from the entities involved in the relationship each have 3 records,then the resulting bridge relation cannot have less than ________ records.
A)0
B)1
C)3
D)9

Accepted Answer

Since the relationship is mandatory on one side, each record on the mandatory side must relate to at least one record on the optional side, resulting in a minimum of 3 records in the bridge relation.

Question 19

Which of the following is NOT true? In a relational table:
A)Two columns can have the same values
B)All column names are different
C)Two rows can have the same values
D)All values in a column are from the same domain

Accepted Answer

In a relational table, each row should ideally represent a unique record, meaning two rows having the exact same values could potentially violate the principle of entity integrity, depending on the context and constraints applied to the table (like a primary key constraint). However, the other statements are generally true: columns can have the same values (A), column names within a table must be unique (B), and all values in a column are expected to be from the same domain or data type (D).

Question 20

If a 1:M relationship is optional on the 1 side and mandatory on the M side,which of the following is true?
A)The resulting foreign key can have null (empty)values
B)The resulting foreign key cannot have null (empty)values
C)The resulting foreign key must have null (empty)values
D)No foreign key is created as a result of mapping such a relationship

Accepted Answer

The resulting foreign key can have null (empty) values because the relationship is optional on the 1 side.

Quiz 3: Relational Database Modeling

An ER diagram that contains two entities involved in two separate M:N relationships will be mapped as how many relations?

If an M:N relationship is optional on both sides,and if both relations resulting from the entities involved in the relationship each have 3 records,then the resulting bridge relation cannot have less than ________ records.

An entity with two multivalued attributes will be mapped as how many relations?

Which of the following is NOT true? Mapping an M:N relationship that has no attributes will result in:

If an M:N relationship is mandatory on both sides,and if both relations resulting from the entities involved in the relationship each have 3 records,then the resulting bridge relation cannot have less than ________ records.

If a 1:M relationship is mandatory on the M side and optional on the 1 side,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side cannot have less than ________ records.

If a 1:M relationship is mandatory on both sides,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side CANNOT have less than ________ records.

If a 1:M relationship is mandatory on both sides,which of the following is true?

If a 1:M relationship is optional on the M side and mandatory on the 1 side,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side CANNOT have less than ________ records.

If a 1:M relationship is optional on both sides,which of the following is true?

Which of the following statements regarding the table below is true? $\begin{array} { | l | l | l |} \hline \text { ColumnA } & \text { ColumnB } & \text { ColumnC } \\\hline\end{array}$

If an entity has three unique attributes,how many primary keys will its mapped relation have?

Which of the following is NOT true? In a relational database:

If a 1:M relationship is optional on both sides,and if the table resulting from the 1 side has 3 records,then the table resulting from the M side CANNOT have less than ________ records.

If a 1:M relationship is mandatory on the 1 side and optional on the M side,which of the following is true?

Relation is a synonym for

Tuple is a synonym for

If an M:N relationship is mandatory on one side and optional on the other side,and if both relations resulting from the entities involved in the relationship each have 3 records,then the resulting bridge relation cannot have less than ________ records.

Which of the following is NOT true? In a relational table:

If a 1:M relationship is optional on the 1 side and mandatory on the M side,which of the following is true?