Chapter Database Processing GearUp: “YOU Don’t Know Anything About Report Writing” • GearUp needs operating data to analyze for cost-cutting decisions • Need to extract and combine data from multiple systems • Will use Access to create reports Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-2 Study Questions Q1: What is the purpose of a database? Q2: What is a database? Q3: What are the components of a database application system? Q4: How database applications make databases more useful? Q5: How are data models used for database development? Q6: How is a data model transformed into a database design? Q7: What is the users’ role in the development of databases? Q8: 2023? Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-3 Q1: What Is the Purpose of a Database? • • • Organize and keep track of things Keep track of multiple themes General rule: Single theme store in a spreadsheet Multiple themes require a database Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-4 A List of Student Grades, Presented in a Spreadsheet Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-5 Student Data Shown in a Form, from a Database Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-6 Q2: What Is a Database? Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-7 Components of a Database Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-8 What Are Relationships Among Rows? Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-9 Sample Metadata (in Access) Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-10 Sample E-R Diagrams Version Crow’s Feet 1:N N:M Version Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-28 Crow’s-Foot Diagram Version Minimum and Maximum Cardinality Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-29 Q6: How Is a Data Model Transformed into a Database Design? Poorly structured Employee table Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-30 Normalizing for Data Integrity Two normalized tables Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-31 Summary of Normalization Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-32 Steps for Transforming Data Model Into a Database Design Construct Adviser table and Student tables with key fields Represent relationships by adding foreign keys Create new table for N:M relationships Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-33 Transforming a Data Model into a Database Design: 1:N Relationship Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-34 Representing an N:M Relationship Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-35 Q7: What Is the Users’ Role in the Development of Databases? • Define what data database must contain • User review of data model is crucial – Does model accurately reflect your view of the business? • • Final approval of data models Devote time to it right Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-36 Q8: 2023? • Volume of database data to grow exponentially • Relational databases will look much different • Use of non-relational data stores, called NoSQL will be more common • Major DBMS vendors lose out to open-source products and shift focus to services supporting open source software like Bigtable, Dynamo, Cassandra? • Database models will be very different Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-37 Guide: No, Thanks, I’ll Use a Spreadsheet • • • • • Databases take time to build Complicated to operate Need IS people to create and keep them running Salesman doesn’t want to share data Spreadsheets sometimes better option, especially if data needs are simple Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-38 Guide: Immanuel Kant, Data Modeler • • • • Perception of reality is based on our perceptive apparatus Brain processes perceptions into something meaningful Human’s model what appears to be Users must determine if a data model fits their perception of reality Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-39 Active Review Q1: What is the purpose of a database? Q2: What is a database? Q3: What are the components of a database application system? Q4: How database applications make databases more useful? Q5: How are data models used for database development? Q6: How is a data model transformed into a database design? Q7: What is the users’ role in the development of databases? Q8: 2023? Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-40 Case Study 5: Fail Away with Dynamo, Bigtable, and Cassandra • Current relational DBMS products not designed for large, multi-server systems • • • NoSQL databases – Dynamo, Bigtable, Cassandra • • Both created to be elastic Amazon: Dynamo Google: Bigtable processes petabytes of data on hundreds of thousands of servers Cassandra used by Facebook, Twitter, Digg, Reddit Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-41 5-42 ... Prentice Hall 5-14 Structured Query Language (SQL) • • SQL (see-quell) – – International standard Used by most popular DBMS SQL statement: – INSERT INTO Student ([Student Number], [Student Name], HW1,... Administration Tasks Copyright © 2014 Pearson Education, Inc Publishing as Prentice Hall 5-16 Using MIS InClass 5: How Much Is a Database Worth? • • • • Data has resale value Data on everything customers... balance in its balance value to file, causing customer’s account copy of customer record changes made by Process A to balance and writes record to file be lost 2 Process B reads same Process B has original