Test 1 Review

Question 1

What is a Key-Value?

Answer 1

Unstructured data great for many types of applications, not typically for businesses.

Question 2

What is a database?

Answer 2

A self describing collection of integrated records.

Question 3

What is a Relational Database?

Answer 3

Stores information grouped into 1+ tables with one/many attributes.
Each attribute contains only one type of data.

Question 4

What are tables?

Answer 4

AKA Class; Typically a single subject, it is where all data/user information is stored in the database. Names must be unique.

Question 5

What are queries?

Answer 5

Used to search and/or manipulate data in a table(s).

Question 6

What are forms?

Answer 6

User friendly way to input and search information in a database.

Question 7

What are reports?

Answer 7

Formats data for printing on paper.

Question 8

What are the elements of a table?

Answer 8

Attributes (columns or fields)

Rows (records)

Question 9

What are some attribute data types?

Answer 9

Number
Text
Date/Time
Attachment
Yes/No
Hyperlink

Question 10

What is a Primary Key?

Answer 10

Identifier for each row (instance) and is often an Autonumber. It is unique and not null and can be comprised of more than one attribute (composite key).

Question 11

What is NULL?

Answer 11

An empty value, not zero or blank.

Question 12

What is a field size?

Answer 12

Numerical value that allows you to determine the field type and size for numbers.

Question 13

What is a format?

Answer 13

Display layout for a field that applies to both numbers and dates.

Question 14

What is an input mask?

Answer 14

A pattern for all data when entering data into a field.

Question 15

What is a caption?

Answer 15

The name of the field when used in the datasheet view.

Question 16

What is a default value?

Answer 16

A value that is automatically entered for a field if the user does not provide a value.

Question 17

What is a validation rule/text?

Answer 17

Rule: only allow data that fits certain criteria to be entered.
Text: a custom message to show when a rule fails.

Question 18

What is a required value mean?

Answer 18

Users must enter a value into the field.

Question 19

What are associations?

Answer 19

Relationships between tables.

Question 20

What are foreign keys?

Answer 20

Used to provide associations between tables and should be related to the primary key in the related table. Always goes on the many side of the relationship.

Question 21

What is normalization?

Answer 21

A set of guidelines for breaking tables apart to eliminate redundancy and reduce potential errors.

Question 22

Most databases never get past 3rd normal form (T/F)

Answer 22

True

Question 23

What are the levels of normalization?

Answer 23

1-5, Domain-Key Normal, and 6th

3rd is aka Boyce-Codd Normal

Question 24

What is de-normalization?

Answer 24

Reconstructing tables for performance or practicality purposes.

Question 25

What is 1st normal form?

Answer 25

Each table should have a primary key with no repeating groups of information within a single table. Each attribute has a single value.

Question 26

What is 3rd normal form?

Answer 26

In 1st and 2nd normal forms, remove any columns that are not dependent on the entire primary key, with exception of names/address, numbers, and dates.

Question 27

What is transitive dependency?

Answer 27

Link between tables where data in one non-key column needs to be changed based on another non-key column (violates 3rd normal form).

Question 28

What is multiplicity?

Answer 28

An indication of how many objects may participate in a given association, used to describe the types of relationships between tables. (1 - +; + - +; 1 - 1)

Question 29

1 - Many Relationship

Answer 29

1 side is always primary key.

Question 30

Many - Many Relationship

Answer 30

Junction table required with primary key and the foreign keys of the 2 tables.