Database Systems

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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

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The Value of Databases

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

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7.1 Basic Data Management Concepts
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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
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Database

• A collection of data organized to meet users
  needs.

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Database Fields

• Fields are set to hold specific types of data.

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Database
A Database is a collection of files/tables
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Database Heirarchy
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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.

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

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

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Relation Types

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

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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.
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Object Oriented Database

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

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7.3 Database Management Systems
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Database Types

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

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Creating a Database

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

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Creating a Database

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

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Database Strengths

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

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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

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7.4 Using Database Systems in Organizations
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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

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Data Stores
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Business Intelligence

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

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7.5 Database Trends
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Databases and the Internet

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

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Distributed Database
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Other Types of Databases

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

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7.6 Managing Databases
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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.

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Chapter 7 Questions?

• 1. What does SQL stand for?
• 2. What type of database is Access?
• 3. What is OO?
• 4. ______ is the process of extracting
  information from a data warehouse.
• Connecting the dots
• 5. ______ is a field that uniquely identifies a
  record.