Question 1

The second step in creating a user view is to represent the user view as a collection of tables.​

Accepted Answer

The second step in creating a user view is to define the view using SQL.

Question 2

The primary key is a unique identifier.​

Accepted Answer

The primary key is a unique identifier that is used to identify each record in a table. It ensures that each record is unique and cannot be duplicated.

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 used to visually represent the entities, attributes, relationships, and constraints of a database. These elements are all described in the DBDL, which is why an E-R diagram is an effective tool for generating a visual overview of the database.

Question 4

​Careful planning in the early stages of the normalization process will usually avoid the need to consider fourth normal form.

Accepted Answer

Fourth normal form is typically only necessary when dealing with complex multi-valued dependencies that cannot be resolved through normalization up to third normal form. By carefully planning and designing the initial schema, many potential multi-valued dependencies can be identified and resolved earlier in the normalization process, making fourth normal form unnecessary.

Question 5

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

Accepted Answer

In DBDL, a table is represented by listing all columns, and underlining the primary key. This helps in identifying the primary key and other columns in the table.

Question 6

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

The information-level design methodology indeed 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.

Question 7

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

Accepted Answer

In an E-R diagram, "m" and "n" are used to denote the cardinality of a relationship, indicating that multiple instances of one entity can relate to multiple instances of another entity, which is a many-to-many relationship.

Question 8

A design that supports all user views is called a constructive design.​

Accepted Answer

A design that supports all user views is called a universal design, not a constructive design. Constructive design refers to a design that is innovative and creative in solving a problem or creating a product.

Question 9

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 10

​In an E-R diagram,a dashed line represents an identifying relationship and a solid line represents a nonidentifying relationship.

Accepted Answer

In an E-R diagram, a solid line typically represents an identifying relationship, while a dashed line represents a non-identifying relationship.

Question 11

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

Accepted Answer

The first step in creating a user view is to understand the requirements and design the view based on user needs, not to normalize tables.

Question 12

In an entity-relationship diagram,rectangles represent foreign keys.​

Accepted Answer

Rectangles represent entities (tables) in an entity-relationship diagram. Foreign keys are represented by diamonds.

Question 13

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

To support a user view or requirement, a database designer must create a set of tables that will store the necessary data in a structured and efficient manner.

Question 14

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 15

A weak entity is a column or collection of columns that could have been chosen as a primary key,but was not.​

Accepted Answer

A weak entity is an entity that cannot be uniquely identified by its own attributes alone and relies on a foreign key relationship with another entity.

Question 16

​There are two types of primary keys that you can use in your database design.

Accepted Answer

A primary key is a unique identifier for a record in a database table, and there is only one type of primary key, though it can be implemented in different ways (e.g., single-column or composite primary key).

Question 17

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

Accepted Answer

Nulls are used to represent missing or unknown values in a database table. It indicates the absence of a value in a column, which can occur due to a variety of reasons such as incomplete records, data entry errors, or simply because the value is not applicable. Nulls are important in database design as they allow for more flexibility and accuracy in handling data.

Question 18

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 are indeed one-to-many, many-to-many, and one-to-one.

Question 19

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 the correct way to create a many-to-many relationship in a relational database. The new table is called a junction table or an association table, and it contains foreign keys that reference the primary keys of the original tables. The combination of these foreign keys becomes the primary key of the junction table.

Question 20

​A foreign 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 foreign key is used to establish a relationship between two tables by referencing the primary key of one table in another table. It is required to either match the value of the primary key in the referenced table or be null.

Quiz 6: Database Design 2: Design Method

The second step in creating a user view is to represent the user view as a collection of tables.​

The primary key is a unique identifier.​

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

​Careful planning in the early stages of the normalization process will usually avoid the need to consider fourth normal form.

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

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.

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

A design that supports all user views is called a constructive design.​

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

​In an E-R diagram,a dashed line represents an identifying relationship and a solid line represents a nonidentifying relationship.

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

In an entity-relationship diagram,rectangles represent foreign keys.​

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

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

A weak entity is a column or collection of columns that could have been chosen as a primary key,but was not.​

​There are two types of primary keys that you can use in your database design.

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

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

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.​

​A foreign 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.

The second step in creating a user view is to represent the user view as a collection of tables.

The primary key is a unique identifier.

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

Careful planning in the early stages of the normalization process will usually avoid the need to consider fourth normal form.

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

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

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

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

In an E-R diagram,a dashed line represents an identifying relationship and a solid line represents a nonidentifying relationship.

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

In an entity-relationship diagram,rectangles represent foreign keys.

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

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

A weak entity is a column or collection of columns that could have been chosen as a primary key,but was not.

There are two types of primary keys that you can use in your database design.

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

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

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.

A foreign 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.