Database Systems

1
Database Systems
Chapter 7

• Basic Data Management Concepts
• Organizing Data in a Database
• Database Management Systems
• Using Database Systems in Organizations
• Database Trends
• Managing Databases

2
The Value of Databases

• Databases and Database Management Systems (DBMS)
  transform large quantities of data into specific
  and valuable information for accomplishing some
  goal.

3
7.1 Basic Data Management Concepts
4
Database Management System (DBMS)

• A DBMS consists of a group of programs that
  manipulate the database and provide an interface
  between the database and the user or the database
  and application programs.

SecureAccess
Front End
Back End
5
Database

• A collection of data organized to meet users
  needs.

6
Database Fields

• Fields are set to hold specific types of data.

7
Database
A Database is a collection of files/tables
8
Database Heirarchy
9
Keys and Primary Key

• Key A field in a record that is used to identify
  the record
• Primary key A field that uniquely identifies a
  record
• A primary key field prevents duplicate records
  from occurring in a table.

10
Primary Keys
Which field would act as the best primary key?
11
Primary Keys
12
Simple but Restrictive DBMS
13
The Database Approach to Data Management
14
7.2 Organizing Data in a Database
15
The Relational Model

• In a relational database, tables are linked
  (related) through common fields.

16
Relation Types

• One-to-many
• Most typical
• Makes use of primary key
• One-to-one
• Many-to-many

17
Data Analysis

• Data analysis is a process that involves
  evaluating data to identify problems with the
  content of a database.
• Consider what would happen if CardNumber were not
  a primary key, and two or more customers had the
  same CardNumber.
• Data Integrity refers to the accuracy of the data
  in a database.

GIGO, or Garbage In Garbage Out, refers to the
fact that inaccurate data entered in a database
will result in inaccurate information produced
from the database.
18
Northwind Database Example

• http//lit.cs.fsu.edu/recitation-notes/nwind.mdb

19
Object Oriented Database

• An object-oriented database encapsulates the data
  and the processing instructions together as
  objects in the database.

20
7.3 Database Management Systems
21
Database Types

• Single User vs. Multiuser
• General-Purpose vs. Special-Purpose
• Open-Source

22
Creating a Database

• A schema is an outline of the logical and
  physical structure of the data and relationships
  among the data in the database.

23
Creating a Database

• A data dictionary provides a detailed description
  of all data used in the database.

24
Database Strengths

• The power of a database and DBMS lies in the
  users ability to manipulate the data to turn up
  useful information.

• Data can be sifted, sorted and queried through
  the use of data manipulation languages.

25
Data Manipulation Language

• A Data Manipulation Language (DML) is a specific
  language provided with the DBMS that allows
  people and other database users to access,
  modify, and make queries about data contained in
  the database, and to generate reports.
• Structured Query Language (SQL) The most popular
  DML.
• SELECT FROM EMPLOYEE WHERE JOB_CLASSIFICATION
  C2

26
7.4 Using Database Systems in Organizations
27
Data Stores

• Data Warehouse A database that holds important
  information from a variety of sources.
• Data Mart A small data warehouse, often
  developed for a specific person or purpose.

• Data Mining the process of extracting
  information from a data warehouse.
• Connecting the dots

28
Data Stores
29
Business Intelligence

• Business Intelligence is the use of data mining
  to help increase efficiency, reduce costs, or
  increase profits.

30
7.5 Database Trends
31
Databases and the Internet

• The Web is frequently used as the Front End of
  DBMSs.

32
Distributed Database
33
Other Types of Databases

• Visual, audio, and unstructured database systems
  organize non-textual data.

34
7.6 Managing Databases
35
Database Administrator

• A database administrator (DBA) is a skilled and
  trained computer professionals who directs all
  activities related to an organizations database,
  including providing security from intruders.

36
Chapter 7 Questions?