5-Topic 4 - Database.pdf

Chapter 05: Organizing and Storing Data Stair, Reynolds and Chesney: Principles of Business Information Systems, Fourth edition (9781473774605) © Cengage Learning 2021  Database The center of almost every information syste...

Chapter 05: Organizing and Storing Data Stair, Reynolds and Chesney: Principles of Business Information Systems, Fourth edition (9781473774605) © Cengage Learning 2021  Database The center of almost every information system. The most common database is the relational database A relational database is a series of related tables, stored together with a minimum of duplication to achieve consistent and controlled pool of data. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Database So, a relational database is made up of several tables. Each table stores the data about someone or something of interest to the firm. This someone or something is known as an entity. (sometimes the data about one entity is stored in two or more tables, and sometimes the data about two or more entities are stored in one table.) For example, a small business selling office furniture might have a customer table to store all the data about their customers, a supplier table to store information about suppliers and an order table that records all the orders that are placed by its customers. In this example, there are three entities – customer, order and supplier. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Relational database A relational database is made up of a number of tables. A table is made up of a number of records. Each record is made up of a number of fields. In loose terms, each table stores the data about someone or something of interest to the firm, known as an entity. Customer is an example. The fields are the specific items of data stored about an entity (name, data of birth, address, etc.). A record collects all the data about one specific entity, the customer John Smith for example For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning Data Entities, Attributes, and Keys (continued) For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Keys Each record must be unique in some way. The primary key is a field that is defined to be unique for each entity. Student ID, Exam ID and Library ID are all primary keys that uniquely identify you. Primary keys are used to join tables: ‘Post’ a primary key into another table to join the two Foreign Key When Primary key is posted into another table to create a relationship between the two, it is called foreign key. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning PK FK Forof For use with Principles use with Principles Business of Business Information Information Systems, 4e Systems, 3e by Stair, Reynolds by Stair,&Reynolds Chesney & Chesney © 2021 Cengage © 2018Learning Cengage Learning  Database design 1 A database design is also known as a data model or a database schema. It is a list of all the tables in the database, along with all the fields, with any primary and foreign keys identified. One approach to database has 4 stages: 1. Identify all entities: Identify all entities you want to store data about. 2. Identify all relationships between entities 3. Identify all attributes )fields( 4. Resolve all relationships: deciding how to implement it. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Forof For use with Principles use with Principles Business of Business Information Information Systems, 4e Systems, 3e by Stair, Reynolds by Stair,&Reynolds Chesney & Chesney © 2021 Cengage © 2018Learning Cengage Learning  Creating and modifying the database » Data definition language (DDL): collection of instructions and commands used to define and describe data and relationships in a specific database. – Allows the database’s creator to describe the data and relationships that are to be contained in the schema. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning Creating and modifying the database » Data Dictionary: A detailed description of all the data used in the database. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Database Output After a database has been set up and loaded with data, it can produce any desired reports, documents. These outputs usually appear in screen displays or hard-copy printout. Another concept is a management reporting system is a system that provides business information. This information can be in the form of reports and/or statements. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Database Management System (DBMS) Creating and implementing the right database system ensures that the database will support both business activities and goals. DBMS: a group of programs used as an interface between a database and application programs or a database and the user. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Database Administration Role of the database administrator (DBA) is to plan, design, create, operate, secure, monitor, and maintain databases The DBA works with both users and programmers For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Data Warehouses & Data Mining Data warehouse: database that collects business information from many sources in the enterprise, covering all aspects of the company’s processes, products, and customers For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Data mining Data mining: information-analysis tool that involves the automated discovery of patterns and relationships in a data warehouse. There are a number of data mining tools and techniques. Association rules algorithms are used to find associations between items in the data. For example, if someone buys eggs, how likely is it that they will also buy cheese? For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Web and Text Mining » Web mining is the application of data mining techniques to discover patterns from the World Wide Web. » Text mining, also referred to as text data mining, roughly equivalent to text analytics, is the process of deriving high-quality information from text. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Business Intelligence Business intelligence (BI): process of gathering enough of the right information in a timely manner and usable form and analyzing it to have a positive impact on business strategy, tactics, or operations – Turns data into useful information that is then distributed throughout an enterprise For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Distributed databases Distributed database – Database in which the data may be spread across several smaller databases connected via telecommunications devices Replicated database – Database that holds a duplicate set of frequently used data For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Online Analytical Processing (OLAP( Software that allows users to explore data from a number of different perspectives. OLAP supports data analysis and decision making and provides query driven data analysis. Each aspect of information ( product, pricing, cost, region, time period) is different dimension. Example: How many washers sold in the East in June compared with other regions? For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning Online Analytical Processing (OLAP) For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Visual, Audio, and Other Database Systems Visual Database: Databases for storing images. Audio Database: Databases for storing sound. Virtual database systems: Allow different databases to work together as a unified database system. For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Summary Relational Database: a collection of tables used to store data Primary Key: a field or set of fields in a record that is used to identify the record Database approach to data management: a pool of related data is shared by multiple application programs Database design: list of tables with primary and foreign keys identified For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Summary (cont.) Database management system (DBMS): group of programs used as an interface between a database and application programs or a database and the user Role of the database administrator (DBA): plan, design, create, operate, secure, monitor, and maintain databases For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning  Summary (cont.) Data warehouse: database that collects business information from all aspects of a company’s processes, products, and customers Data mining: information-analysis tool for the automated discovery of patterns and relationships in a data warehouse For use with Principles of Business Information Systems, 4e by Stair, Reynolds & Chesney © 2021 Cengage Learning