1004INT Information Systems

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1004INT Information Systems

• Week 10
• Databases as Business Tools

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Last week in context

• Week 8 The System Development Life Cycle (SDLC)
• Phases Planning, Analysis, Design,
  Implementation, Maintenance
• Data Flow Diagrams (DFDs)
• Context diagrams and external entities
• Next The most important piece of business
  software the Database
• Data design, tables and relationships

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Week 10 Objectives

• Develop an understanding of how business entities
  are uniquely defined
• To understand the relationships between business
  entities
• To understand how relational databases are used
  to store data and use it to create business
  information
• How to use MS Access creating tables
  relationships (related to tutorial exercises)

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Activities

• Presentation on Databases and Database Management
  Short Quiz
• Discussion of Entities, Relationships, and
  Information Design Short Quiz
• Workshop Using Access tools to create a working
  database

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Quiz 1 - Databases

• What does database software allow you to do?
• Allows you to create and manage data by adding,
  updating, deleting, and retrieving it
• Why are network databases so important?
• Reduced redundancy and increased accuracy
• What are the elements in a data hierarchy?
• Tables
• Records (rows)
• Fields / Attributes (columns)
• Data items (different types and sizes)

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Quiz 1a Data In Info Out

• Give two ways to get data in to a database?
• Edit the tables directly, or use an input form
• Give two ways to get information out of a
  database?
• Queries (SQL), or Reports

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Quiz 1b Quality and organisation

• What does DBMS stand for?
• DataBase Management System (or Software)
• How are data and information different?
• Data is raw facts and figures, it becomes
  information when it is organized to be useful
• What does GIGO mean?
• Garbage In Garbage Out
• The quality of the information coming out is as
  good as the quality of the data going in

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Quiz 1c Value

• Qualities of valuable information?
• Accuracy (correct and up to date)
• Verifiability (can be checked)
• Timeliness (when it is needed)
• Organization (useful format)
• Accessible (easily available)
• Useful (helps to make good decisions)
• Quantity?
• Cost?

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Quiz 2 - Entities

• What is an entity?
• Things that business keeps record of
• What data is required to define an entity?
• Enough relevant information
• What is key data?
• Uniquely identifying data
• What is an ERD?
• Entity-Relationship Diagram

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What you should take away today

• (Information) Databases are (arguably) the most
  important business software
• Business data is collected and managed to create
  useful information using a Database
• Database tables (files) are created for each
  entity existing in the business.
• Tables have relationships as denoted in relevant
  Entity Relationship Diagrams (ERDs)
• MS Access tools and tips for lab work