Question 1

The use of an "m" and an "n" in an E-R diagram indicates a many-to-many relationship.

Accepted Answer

True

Question 2

In an entity-relationship diagram,there is no way to visually determine the primary key.

Accepted Answer

In an entity-relationship diagram, primary keys are typically underlined or marked with a special symbol to visually distinguish them from other attributes.

Question 3

When you use an E-R diagram to represent a database,it visually illustrates all the information listed in the DBDL.

Accepted Answer

An E-R diagram is a visual representation of the information contained within a database, including entities, attributes, relationships, and constraints, as outlined in the DBDL.

Question 4

The simplest way to implement a one-to-one relationship is to treat it as a one-to-many relationship.

Accepted Answer

The answer of The simplest way to implement a one-to-one...

Question 5

The second step in creating a user view is to normalize the tables.

Accepted Answer

Normalizing tables involves breaking them down into smaller, more focused tables that are linked together through relationships. This is an important step in creating a user view because it helps ensure data consistency and reduce redundancy.

Question 6

In a one-to-many relationship,the primary key of the "many" table becomes the foreign key of the "one" table.

Accepted Answer

In a one-to-many relationship, the primary key of the "one" table is used as a foreign key in the "many" table to establish the relationship.

Question 7

When you combine third normal form tables,the result will always be in third normal form.

Accepted Answer

Combining third normal form tables can introduce transitive dependencies or other forms of redundancy, potentially violating the rules of third normal form.

Question 8

An entity that depends on another entity for its own existence is called a weak entity.

Accepted Answer

A weak entity is an entity that cannot be identified without the existence of another entity. It depends on the existence of a strong entity, called its owner or identifying entity, to give it context and meaning.

Question 9

The basic relationships among entities are: one-to-many,many-to-many,and one-to-one.

Accepted Answer

This statement is true. The basic relationships among entities in a database are one-to-many, many-to-many, and one-to-one. These relationships define how data is organized and connected within the database.

Question 10

The information-level design methodology involves representing the individual user view as a collection of tables,refining them to eliminate any problems,and then merging them into a cumulative design.

Accepted Answer

This statement accurately describes the information-level design methodology.

Question 11

The second step in creating a user view is to identify all keys in the tables.

Accepted Answer

The second step in creating a user view is typically to identify the entities and relationships, not to identify all keys in the tables. Identifying keys usually comes later in the process.

Question 12

A secondary key is a column or collection of columns in one table that is required to match the value of the primary key for some row in another table,or be null.

Accepted Answer

A secondary key is not required to match the primary key in another table; it is used for indexing and improving query performance within the same table. The term you're describing is a foreign key.

Question 13

In DBDL,you represent a table by listing all columns and then underlining the primary key.

Accepted Answer

This is correct, a table in DBDL is represented by listing all columns and underlining the primary key.

Question 14

You create a many-to-many relationship by creating a new table whose primary key is the combination of the primary keys of the original tables.

Accepted Answer

This is correct. The new table, known as a junction or linking table, will have a primary key made up of foreign keys from each of the original tables. This allows for multiple records from each table to be linked to multiple records in the other table.

Question 15

When provided with a user view or some sort of stated requirement,you must develop a collection of tables that will support it.

Accepted Answer

This is true. When designing a database, it is necessary to determine the appropriate tables and their relationships in order to store and organize the required data. This process often begins with a user view or set of stated requirements.

Question 16

An entity that exists to implement a many-to-many relationship is called a multivalued entity.

Accepted Answer

An entity that exists to implement a many-to-many relationship is called a "junction table" or "associative entity," not a multivalued entity.

Question 17

When creating user views,a "user" can be a report that the system must produce,or a type of transaction the system must support.

Accepted Answer

User views can represent either a report or a transaction that the system must support.

Question 18

A design that supports all user views is called a normalized design.

Accepted Answer

A normalized design is a design that eliminates redundancies and inconsistencies in data structure by organizing them into separate tables with relationships between them. It does not necessarily support all user views, but rather focuses on data integrity and efficient storage. Meeting all user views may require additional design considerations or the use of alternative approaches.

Question 19

Entity integrity is the property that states that a secondary key in one table is required to match the value of the primary key for some row in another table or is required to be null.

Accepted Answer

Entity integrity ensures that the primary key of a table is unique and not null, while the described property is related to referential integrity, which involves foreign keys.

Question 20

Nulls are used when a value is either unknown or inapplicable.

Accepted Answer

Nulls are used to represent missing or unknown data. They are also used to indicate that a value is not applicable or does not exist.

Quiz 6: Database Design 2: Design Method