Download - 1Database Design Introduction
-
8/10/2019 1Database Design Introduction
1/24
Introduction
Database Design
-
8/10/2019 1Database Design Introduction
2/24
What is a Database
Databasecollection of organized data
Legacy databasethe database is old and been
in the company for quite some time
Examples of databases:Address books
Telephone directory
Library information
Bookstores Finance softwares
maps
-
8/10/2019 1Database Design Introduction
3/24
-
8/10/2019 1Database Design Introduction
4/24
OLTP and OLAP
Online Transaction Processing(OLTP)
Database used to process data in a regular basis
Examples: grading system, sales, reservation
Online Analytical Processing(OLAP)
Supply end users with response to queries being
submitted
Concerned with bulk data loads
Decision Support Systems and Data Warehouses
-
8/10/2019 1Database Design Introduction
5/24
Database Environment
Mainframe environmentconsists of powerfulmainframe computer that allowed multiple user
connections. Multiple terminals are networked to
the main computer
Client/server environmentinvolves a main
computer , called the server, and one or more
personal computers are connected into it
Internet computing environmentrelies on the
internet for networks, the server is called the Web
Server
-
8/10/2019 1Database Design Introduction
6/24
Where Does a Database
Originate?
Business rules
Business processes
Data
Analysis Entities
Attributes
Re-engineering
-
8/10/2019 1Database Design Introduction
7/24
Business Rules
It affects the business in many ways
Tells how data is created, stored, and retrieved,
and manipulated
Categories of business rules:-database oriented
-application oriented
-
8/10/2019 1Database Design Introduction
8/24
Business Processes
Daily/timed activities of the company
Can be manual or automated
Example:
1. Order is received from customer2. Inventory is checked for availability
3. Customers order if confirmed
4. Warehouse is contacted
5. Product and invoice are shipped to the
customer
-
8/10/2019 1Database Design Introduction
9/24
Information and Data
Informationknowledge of something
Datainformation related to the organization
Types of data:
Static/historical
accessed only when needed Dynamic/transactionalused more often
-
8/10/2019 1Database Design Introduction
10/24
Requirements Analysis
Analyzing the needs of a business
Rules and process are considered aside from
data
Some of basic information needed: Objectives and goals pertaining to the system
Proposed requirements
Business process and rules
Documents of current information
-
8/10/2019 1Database Design Introduction
11/24
Entities and Attributes
Entities
Business object that represent a group, or
category of data
Examples:titles, topics
Attributes
Sub group of information within an entity
Example: within a book title there can be theactual title, the publisher, and author
-
8/10/2019 1Database Design Introduction
12/24
Business process re-engineering
Task of reworking process in order to streamlinethe operations
Redesigning the entire system
Improvement of methods
-
8/10/2019 1Database Design Introduction
13/24
Elements of a Database
Schema
Schema objects
Tables
Fields and columns Records or rows
Keys
Relationships
Data types
-
8/10/2019 1Database Design Introduction
14/24
Database Schema
Schemagroup of related objects in a database Conceptual/logical model
Internal/physical model
External/view model
-
8/10/2019 1Database Design Introduction
15/24
Tables
Primary unit of physical storage in the database
Types of data:
Data tables
Join tables
Subset tables
Validation tables
-
8/10/2019 1Database Design Introduction
16/24
Columns
Category of information in the database
Represents related part of a table
Smallest logical structure
-
8/10/2019 1Database Design Introduction
17/24
Rows
Collection of all columns in a table associatedwith a single occurrence
Single record in a table
-
8/10/2019 1Database Design Introduction
18/24
Data Types
Alphanumeric
Numeric
Date and Time
Boolean Character Large Objects
Binary Large Objects
-
8/10/2019 1Database Design Introduction
19/24
Database Integrity
Insurance of accurate data in database
Constraintsvalidate the values of the data
Referential integrityprocess of ensuring that
data is consistent between related tables
-
8/10/2019 1Database Design Introduction
20/24
-
8/10/2019 1Database Design Introduction
21/24
Relationships
Relationships reduce data redundancy
Normalizationprocess of reducing data
redundancy
Types of relationships:
One-one
One-many
Many-many
-
8/10/2019 1Database Design Introduction
22/24
Design Methodology
Process of designing a database with a plan
Advantages:
Step by step guide
Minimal trial and error
Easier documentation
Easier to modify the database
-
8/10/2019 1Database Design Introduction
23/24
Application Design
Creating an interface for the end user throughwhich the database can be accessed
Consists of set of forms that allow the end user to
manipulate data
-
8/10/2019 1Database Design Introduction
24/24
Characteristics of a good
database
Storage needs met
Available data
Secured data
Accurate and easy to manageAcceptable performance to the user
Minimal redundant data