Mid Term

Question 1

What does DML stand for?

Answer 1

Data Manipulation Language

Question 2

What is the purpose of DML operations?

Answer 2

To manipulate the table.

Question 3

3 types of DML operations?

Answer 3

1. Insert
2. delete
3. Update

Question 4

A notation for describing data or information

Answer 4

A data model

Question 5

What are 3 ways a data model can describe data?

Answer 5

1. Structure of the data
2. Operations on the data
3. Constraints on the data

Question 6

Represents data in 2-D table (rows and columns)

Answer 6

Relations

Question 7

True me false: Table, entity, and relation are the same?

Answer 7

True

Question 8

The columns of a relation are called?

Answer 8

Attributes

Question 9

What do attributes describe?

Answer 9

The meaning of entries in the column

Question 10

What is a logical structure for data?

Answer 10

Schema

Question 11

The set of schemas for the relations in a relational database are called?

Answer 11

Relational Database Schema

Question 12

The name of a relation and the set of attributes for a relation?

Answer 12

Schema (for relation)

Question 13

What is ‘a set’?

Answer 13

The attributes in a relation schema

Question 14

True or False: Rows and Tuples are the same thing?

Answer 14

True

Question 15

What are tuples?

Answer 15

The rows of a relation, minus the header.

Question 16

What is the relationship between an attribute and a domain?

Answer 16

Each attribute of a relation is a domain

Question 17

What are the two parts of a relation?

Answer 17

1. Schema
2. Instance

Question 18

Formal term for ‘Table’

Answer 18

Relation

Question 19

Formal term for ‘Column’

Answer 19

Attribute

Question 20

Formal term for ‘Row’

Answer 20

Tuple

Question 21

Formal term for values in a Column

Answer 21

Domain

Question 22

Formal term for Table Definition

Answer 22

Relation Schema

Question 23

Formal term for populated Table

Answer 23

Relation Instance/Extension

Question 24

Properties of relations

Answer 24

1. No duplicate tuples
2. Tuples have no order
3. No duplicate attributes
4. Attributes have no order
5. Every tuple must have attribute values from each of the domains or NULL

Question 25

T/F: Tuples are unordered

Answer 25

True

Question 26

T/F: Attributes are unordered

Answer 26

True

Question 27

What are two ways to declare a key in the CREATETABLE statement?

Answer 27

1. Declare 1 attribute when listed in the relation schema 2. Add an additional declaration identifying a listed attribute or set of attributes which form the key

Question 28

A specific type of field in a relational database that can identify each unique record independently of any other data.

Answer 28

Candidate Key

Question 29

A column or group of columns in a relational database table that provides a link between data in two relations.

Answer 29

Foreign Key

Question 30

A special relational database table column (or combination of columns) designated to uniquely identify each table record.

Answer 30

Primary Key

Question 31

a candidate key that consists of two or more attributes that together uniquely identify an entity occurrence

Answer 31

Composite Key

Question 32

What is a stored relation?

Answer 32

Table

Question 33

Relations defined by computation. They are not stored but are constructed when needed.

Answer 33

Views

Question 34

Relations created by SQL language processor when executing queries and data modifications.

Answer 34

Temporary Tables

Question 35

Data objects that either identify or describe entities...

Answer 35

Attributes

Question 36

What are two types of attributes?

Answer 36

1. Simple Attribute 2. Composite Attribute

Question 37

An attribute that cannot be sub-divided

Answer 37

Simple Attribute

Question 38

An attribute that can be sub-divided to yield additional attributes

Answer 38

Composite Attribute

Question 39

An attribute that is not physically stored within the database; derived by algorithm

Answer 39

Derived Attribute

Question 40

An attribute that can only have a single atomic value

Answer 40

Single-valued Attribute

Question 41

An attribute that can have many values

Answer 41

Multi-valued Attribute

Question 42

Connections among two or more entity sets are called...

Answer 42

Relations

Question 43

The maximum number of times an instance in one entity can be associated with instances in a related entity

Answer 43

Cardinality

Question 44

The minimum number of times an instance in one entity can be associated with an instance in a related entity

Answer 44

Modality

Question 45

Cardinality values

Answer 45

One or Many

Question 46

Modality Values

Answer 46

One or Zero

Question 47

In ER Diagrams entity sets are represented by...

Answer 47

Rectangles

Question 48

In ER Diagrams attributes are represented by...

Answer 48

Ovals

Question 49

In ER Diagrams relationships are represented by...

Answer 49

Diamonds

Question 50

Requires that if a value of one attribute of a relation references a value of another attribute, then the referenced value must exist.

Answer 50

Referential Integrity Constraint

Question 51

A collection of data that is managed by a DBMS...

Answer 51

Database

Question 52

A software tool for managing data in a database

Answer 52

Database Management System (DBMS)

Question 53

If a DMBS is for a relational database?

Answer 53

RDMBS

Question 54

How does DMBS allow users to define schema (structure)?

Answer 54

Data Definition Language (DDL)

Question 55

How does DMBS allow users to query (question) or modify the data?

Answer 55

Data Manipulation Language (DML)

Question 56

What are the two types of languages used by DMBS?

Answer 56

1. Data Definition Language (DDL) 2. Data Manipulation Language (DML)

Question 57

In SQL, what is projection?

Answer 57

When you add criteria