Information-Systems-for-Business-Beyond-Chapter-5.pptx

Information-Systems-for-Business-Beyond-Chapter-7.pptx

1. Information Systems for Business & Beyond Chapter 5- Data Unless otherwise noted, this work is licensed under a Creative C ommons Attribution- NonCommercial - ShareAlike 4.0 International (CC BY-NC-SA 4.0) license . Feel free to use, modify, reuse or redistribute any portion of this presentation.

2. 5.1 Learning Objectives Upon successful completion of this chapter, you will be able to: Define the term database; Describe the role of a database management system; Explain the difference between a relational and flat file database; Outline the levels of the data hierarchy; Describe the different data types; Identify and apply the steps to create a simple relational database; and Discuss the advantages of the database approach.

3. 5.2 Big Data Big Data by Camelia Boban licensed under CC-BY-SA

4. 5.3 Databases A database is an organized collection of related information.

5. 5.3 Databases A Database Management System (DBMS) is software for creating, storing, maintaining, and accessing database files.

6. 5.4 Database Models There are many database models such as, hierarchical and object-oriented. Relational databases are the most popular. A relational data model organizes data into inter-related tables. Relational databases are easy to understand and use, and are often contrasted with a flat file database which contains only one file/table, with no relationships.

7. 5.4 Database Models I

8. 5.4 Database models II

9. 5.5 Data Hierarchy

10. 5.5 Data Types When defining the fields in a database table, we must give each field a data type. Some of the more common data types are: Text Number Boolean Date/Time Currency Paragraph Text Graphics

11. 5.6 Designing a Database The first step in database design is data modelling. This step provides a high level conceptual representation of the database structure. Data modelling includes capturing the Entities Relationships Constraints

12. 5.6 Designing a Database A primary key must be selected for each table in a relational database. This key is a unique identifier for each record in the table. A foreign key is a field in one table that connects to the primary key data in the original table.

13. 5.6 Normalization When designing a database, one important concept to understand is normalization. In simple terms, to normalize a database means to design it in a way that: 1) reduces data redundancy; and 2) ensure data integrity.

14. 5.7 Why Databases? Data is a valuable resource! Databases help with the following: Data accuracy Efficiency Data integrity Data sharing Security and recovery

15. 5.8 Database Manipulation Database Manipulation is the use of a programming language to modify data in a database to make it easier to view or for the purpose of decision making. SQL (often pronounced sequel) stands for Structured Query Language, and is the most common language for creating and manipulating databases.

16. 5.9 Key Takeaways I A database is an organized collection of related data. A database management system (DBMS) is a software application that is used to create and manage databases, and can take the form of a personal DBMS, used by one person, or an enterprise DBMS that can be used by multiple users Relational databases are the most widely used type of database, where data is structured into tables and all tables must be related to each other through unique identifiers.

17. 5.9 Key Takeaways II Designing a relational database involves determining how the data is organized into tables, setting primary keys and creating relationships among the tables. Normalization is the process of designing a database to reduce redundancy and ensure integrity. The database approach allows for the control of redundant data, data integrity, data sharing, and security and recovery. There are many data types, and it is important to use the correct one.