1004INT Information Systems Week 10 Databases as Business Tools

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

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)

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

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? 1.Tables 2.Records (rows) 3.Fields / Attributes (columns) 4.Data items (different types and sizes)

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

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

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?

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

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