Database Vocab

Question 1

Define: Database

Answer 1

An organized or structured collection of data, typically stored in electronic format

Question 2

Define: CRUD

Answer 2

An acronym that stands for Create, Read, Update, and Delete. These are features of any database.

Question 3

Define: Relational Database Management System

Answer 3

Software that manages data in an organized or structured way.

Question 4

Define: Table

Answer 4

A two-dimensional collection of data.

Question 5

Define: Relational Database

Answer 5

A database in which all data is stored in related tables with rows and columns

Question 6

Define: Relationship

Answer 6

A natural association between or two or more entities.

Question 7

Define: Column

Answer 7

A set of data values(or attributes)all of a single type.

Question 8

Define: Row

Answer 8

Holds the fields or attributes for a specific entity. Also called a record or a tuple.

Question 9

Define: Attribute

Answer 9

a property or description of an entity.

Question 10

Define: Domain

Answer 10

a set of possible values for an attribute.

Question 11

Define: Field

Answer 11

the smallest units of information you can access in a database

Question 12

Define: Record

Answer 12

a group(row) of fields within a table that are relevant to a specific entity

Question 13

Define: Entity

Answer 13

An object in the real world that is distinguishable from other objects and has unique characteristics or attributes.

Question 14

Define: Entity Set

Answer 14

A collection of entities having the same characteristics or attributes

Question 15

Define: Instance

Answer 15

A single entity of an entity set

Question 16

Define: ERD

Answer 16

Acronym for Entity Relationship Diagram. An ERD is a diagram (or model) of a database that shows all tables and relationships between tables

Question 17

Define: Relationship

Answer 17

A natural association between entities (objects)

Question 18

Define: One-to-one Relationship

Answer 18

An instance of entity A is related to only one instance of entity B

Question 19

Define: One-to-many Relationship

Answer 19

An instance of entity A is related to more than one instance of entity B

Question 20

Define: Many-to-many relationship

Answer 20

More than one instance of entity A is related to more than one instance of entity B

Question 21

Define: Primary Key

Answer 21

An attribute (column)or combination of attributes which can be used to uniquely identify one row from any other row in the table.

Question 22

Define: Simple key

Answer 22

A primary key, like Part Number, which contains only one attribute (column)

Question 23

Define: Composite key

Answer 23

A primary key which is made from the combination of more than one attribute (column)

Question 24

Define: Foreign key

Answer 24

A column or combination of columns that is used to establish and enforce a link between the data in two tables.

Question 25

Define: Natural key

Answer 25

A key that is formed of attributes that already exist in the real world

Question 26

Define: Synthetic(Surrogate)Key

Answer 26

Keys that don't have a natural relationship with, and are not derived from, the rest of the columns in a table

Question 27

Define: Normalization

Answer 27

The process of organizing data in order to reduce redundancy by dividing a database into two or more tables and then defining table relationships.

Question 28

Define: Null

Answer 28

The word used to indicate that a field in a record is empty

Question 29

Define: Junction (bridge)table

Answer 29

A table used to implement many-to-many relationships

Question 30

Define: SQL

Answer 30

Structured Query Language. A language written specifically to implement relational databases.

Question 31

Define: Query

Answer 31

An inquiry that returns information back from the database that meets certain criteria.

Question 32

Define: Data Definition Language (DDL)

Answer 32

A subset of SQL that contains SQL statements to create or delete databases and tables.

Question 33

Define: Data Manipulation Language (DML)

Answer 33

A subset of SQL that contains SQL statements to add, update or delete data from tables.

Question 34

Define: Data Query Language (DQL)

Answer 34

A subset of SQL that contains SQL statements to structure queries to retrieve specific data from a database.

Question 35

Define: Data Control Language (DCL)

Answer 35

A subset of SQL that contains SQL statements that provide administrative control of databases.

Question 36

Define: Entity integrity

Answer 36

Entity integrity means that every table must have a primary key

Question 37

Define: Referential integrity

Answer 37

A foreign key must have a matching primary key or it must be null

Question 38

Define: Atomic value

Answer 38

A value that is indivisible as far as the relational model is concerned

Question 39

Define: Schema

Answer 39

The structure or design of a database

Question 40

Define: Index

Answer 40

A data structure that improves the speed of data retrieval operations on a database table

Question 41

Define: Cardinality

Answer 41

The number of occurrences in one entity which are associated (or linked) to the number of occurrences in another entity

Question 42

Define: Tuple

Answer 42

A row or a record of a table.