Fundamentals of Database System

Table definition

• Schema of relation

Include all qualified records from the left table in the join condition even if they do not have matching records in the right table.

• LEFT JOIN

Column header / field

• Attributes

Null means a value is unknown.

• True
• False

Used to control data access

• DCL

The interface presents a menu that lead to a user through request.

• Menu-based Interfaces for Web Clients or Browsing

It is the number of attributes in a relation.

• DEGREE OF RELATION

Each entity instance of one entity class is related to a multiple entity instance of another entity class; and vice versa.

• Many-to-Many

_____ means missing value.

• NULL

Used to define and modify data structures

• DDL

AND operator displays a record if all the conditions separated by AND are TRUE.

• True
• False

Entity Instance is an instance of a particular entity.

• True
• False

Logical Design – transforming the ERD into relational model.

• True
• False

Physical data models is a concept that shows how the data is stored on the computer.

• True
• False

The relational model (RM) was first described by Edgar F. Codd

• True
• False

It is a command used or a request for information from a database.

• QUERY

A single entity instance of one entity class is related to a single entity instance of another entity class.

• One-to-One

Relational Model is a table with columns and rows.

• True
• False

SQL is not a Programming Language.

• True
• False

Composite attribute can be divided into more attributes.

• True
• False

Null means zero

• True
• False

maximum of all or selected values

• max

To sort the records in descending order, use the DESC keyword.

• True
• False

number of all or selected values

• count

Display a form to be fill out by the user.

• Forms-based Interfaces

They are liable for identifying the data to be stored within the database and for selecting appropriate structures to represent and store this data.

• DATABASE DESIGNERS

Cross Join – Used the foreign key as the matching criteria

• True
• False

Relationships can't have attributes.

• True
• False

There’s no difference between the description of database and the database itself.

• True
• False

A single entity instance of one entity class is related to a multiple entity instance of another entity class.

• One-to-Many

Use to get aggregation results for different groups of records.

• GROUP BY

Used to performed or rollback the changes that we made in the database using DML commands.

• Transaction Control Language (TCL)

DML - Manipulate data using commands: insert, update and delete

• True
• False

Entity Relationship Diagram (ERD) was proposed by _____

• DR. PETER CHEN

All possible column values

• Domain

Used to manage data within the object schema.

• Data Manipulation Language (DML)

minimum of all or selected values

• min

A displayed schema is called Schema figure.

• True
• False

It is a combination of symbols and operators that returns a single value.

• EXPRESSION

For each entity instance the value of the identifier attribute is Unique.

• True
• False

AND operator displays a record if all the conditions separated by AND are FALSE.

• True
• False

Data Manipulation Language is use for manipulating data in a database.

• True
• False

The interface allows users to access their data through their mobile phone or mobile device.

• Applications for mobile devices

The participation of an entity in the relationship is optional.

• Optional

Level of database design use to create database.

• PHYSICAL DESIGN

Composite Attribute can be calculated from other attributes.

• True
• False

Describes how entities are related.

• RELATIONSHIPS

OR operator displays a record if any of the conditions separated by OR is TRUE.

• True
• False

DDL - Schema: databases, tables, views and many more

• True
• False

We call the database and DBMS software together as a _____

• DATABASE SYSTEM

Include all qualified records from the right table in the join condition even if they do not have matching records in the left table.

• RIGHT JOIN

DCL - Use the command: Permissions

• True
• False

Is an instance of a particular entity.

• ENTITY INSTANCE

Attribute is a name for a set of similar things that you can list. Like objects, events, people.

• True
• False

Columns or expressions can be in the SELECT clause only if they are in the GROUP BY clause.

• True
• False

A process of producing a set of tables (relations) with a proper attribute.

• NORMALIZATION

It is a question or an inquiry, sometimes loosely used for all types of interactions with databases.

• QUERY

We use _____ to give column another name.

• ALIAS

Used to give or control privilege in a database.

• Data Control Language (DCL)

SQL is used to retrieve data from relational databases.

• True
• False

sum of all or selected values

• sum

The participation of an entity in the relationship is mandatory.

• Mandatory

Numeric

• Integer

DDL used to control data access.

• True
• False

Used for creating tables, schema etc. in database.

• Data Definition Language (DDL)

Like Web search engines (engine like Google), which the user can specify a string or any keywords and expect to get a relevant result.

• Keyword-based Database Search

Tables

• name, primary key

Include all qualified records from both tables in the join condition.

• FULL JOIN

Attribute describes an entity class.

• True
• False

It is a stricter form of 2nd and 3rd normal form

• Boyce Codd Normal Form (BC/NF)

Compound Conditions use logical operators to filter or connect multiple criteria.

• True
• False

Displays a record if any of the conditions separated by OR is TRUE.

• OR OPERATOR

Records that have matching records from two (2) tables

• INNER JOIN

This relationship exists if they are independent or different to each other.

• MULTIPLE RELATIONSHIPS

Structured Query Language is a command use by relational database management system to perform database operations.

• True
• False

Multi-value dependency

• 4th Normal Form (4NF)

Use to retrieve data from multiple tables.

• TABLE JOIN

Used to retrive data and manipulate data

• DML

Facts that can be recorded and that have implicit meaning.

• DATA

A thing that shares a common attribute.

• ENTITY CLASS

Boolean

• true/false

Data abstraction is the data type, relationships and constraints that apply to the data.

• True
• False

NO Partial Dependency

• 2nd Normal Form (2NF)

Constraints

• all kinds of keys

Minimum Cardinality describes the minimum number of entity instances that must participate in a relationship.

• True
• False

Used to sort the result.

• ORDER BY KEYWORD

It is needed when minimum cardinality is optional on a table.

• OUTER JOIN

Asterisk (*) means all or a list of _____

• COLUMNS

It is between high-level and low-level data models.

• REPRESENTATIONAL OR IMPLEMENTATION DATA MODELS

It is a collection of related data.

• DATABASE

Columns

• name, data type, size, value range

Indirect relationship causes functional dependency.

• TRANSITIVE DEPENDENCY

Data model is a collection of concepts that is used to describe the structure of a database.

• True
• False

It is the number of tuples in a relation.

• CARDINALITY OF RELATION

NO “repeating groups” (columns)

• 1st Normal Form (1NF)

Row

• Tuples

An attribute that has a multiple value.

• MULTI-VALUE ATTRIBUTE

Entities can be related indirectly by two (2) relationships.

• TRANSITIVE RELATIONSHIP

In SQL the command language used is like an Spanish language.

• True
• False

A non-key attribute is dependent on part of a composite primary key.

• PARTIAL DEPENDENCY

No primary key can be null.

• True
• False

Maximum Cardinality describes the maximum number of entity instances in the relationship.

• True
• False

Who is responsible in administering the primary and secondary resource in the database?

• DATABASE ADMINISTRATOR

A computerized system that permits users to create and maintain a database.

• DATABASE MANAGEMENT SYSTEM

An Expression can be a single constant, column, variable, or scalar function.

• True
• False

Controlling Redundancy is used to improve the performance of queries.

• True
• False

Database System automatically takes care of backup and recovery.

• True
• False

The table is in a 2NF if there's NO Partial Dependency.

• True
• False

An Expression can't be a number, columns, literals, functions connected by operators

• True
• False

Date

• Time

Its is one or more columns of a relation or table that is used to identify a record.

• KEY

The table is in a 1NF if It satisfies the definition of a relation.

• True
• False

Internal Level describes the physical storage structure of the database.

• True
• False

Use _____ if there is ambiguity when distinguishing a column.

• QUALIFIERS

It describes how entities are related to each other.

• RELATIONSHIP

NO Transitive Dependency

• 3rd Normal Form (3NF)

Character

• Text

Table

• Relation

average of all or selected values

• avg

People whose jobs require access to the database for querying, updating, and generating reports.

• END USERS