1. 5장
Database Processing

2. This Could Happen to You
• Dee selected Movable Type
application program
• Needs database program to store blog
– Consultant suggested MySQL
– Network standardized on Oracle
• May not be able to run Movable Type
• Will require revision of labor estimates
– IT resists installing MySQL
5-2

3. Q1: What Is the Purpose of a
Database?
• To organize and keep track of things
• Spreadsheets do that too
– Keep lists of single concept
– Example: Student test scores in a course
• Databases
– Keep lists that involve multiple themes/concepts
– Examples: Student grades, grades for all courses in a
department, courses offered in all departments, faculty
records, and so on
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4. Q2: What Does a Database Contain?
• Self-describing collection of integrated records
• Hierarchy of data elements
– Bytes/data are grouped into columns/fields
– Columns grouped into rows/records
– Rows are grouped into tables/files
• Collection of tables plus relationships among rows
– Also includes “metadata”
• Describes the structure of the database
• A database is a structured collection of records or
data that is stored in a computer system so that a
computer program or person using a query
language can consult it to answer queries.
5-4

5. Student Table
(also called a file)
5-5

6. Relationships Among Records
• Values in one table may relate to rows/records in
other tables
• Keys
– Column(s) that identify unique row in table
– Each table has a key
• Foreign keys
– Keys of a different table than the one in which they reside
• Relational databases
– Databases using tables, keys, and foreign keys
5-6

7. Example of Relationships
Among Rows
Figure 5-6
5-7

8. Metadata
• Database is self-describing
– Contains descriptions of its data
• Metadata
– Data that describe data
– Make databases more useful
– Make databases easier to use
• Describe data
– Data type
– Field name
– Field properties
5-8

9. Q3: What Is a DBMS and
What Does It Do?
• Database management system (DBMS)
– Program that creates, processes, and administers database
– Usually licensed from vendors
– Examples: Microsoft Access, Oracle, MySQL, DB2
• DBMS and database are two different things
– Database is a structured collection of records or data that is
stored in a computer system so that a computer program or
person using a query language can consult it to answer
queries. The computer program used to manage and query
a database is known as a database management system
(DBMS).
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10. Components of a Database
Application System
5-10

11. Database Management Systems
• DBMS used to create tables, relationships in
databases
• Applications use DBMS to read, insert,
modify, and delete data
– Structured Query Language (SQL)
• International standard for processing database
5-11

12. Creating the Database and Its Structure
5-12

13. Processing the Database
• Four DBMS operations
1. Read data
2. Insert data
3. Modify data
4. Delete data
• Structured Query Language
INSERT INTO Student
([Student Number], [Student Name], HW1, HW2,
MidTerm)
VALUES
(1000, ‘Franklin, Benjamin’, 90, 95, 100)
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14. Administering the Database
• DBMS security features used to set up user
accounts, passwords, permissions,
processing limits
– Permissions – data access rights for specific users
or groups of users
• Database backup and replication, adding
structures, removing unneeded data
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15. Q4: What Is a Database Application?
• Collection of forms, reports, queries, and
application programs that process a database
• Databases can have multiple applications
• Applications can have multiple users
5-15

16. Use of Multiple Database Applications
5-16

17. Forms, Reports, and Queries
• Forms
– Used to read, insert, modify, and delete data
• Reports
– Show data in structured context
– May compute values
• Queries
– Are a means of getting answers from database
data
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18. Database Application Programs
• Application programs
– Process logic specific to a business need
– May enable database processing over Internet
to:
• Serve as intermediary between Web server and
database
• Respond to events
• Read, insert, modify, delete data
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19. Example of a Query
5-19

20. Q5: What Is the Difference Between an
Enterprise DBMS and a Personal DBMS?
• Enterprise DBMS
– Processes large organizational and workgroup
databases
– Supports many users (thousands plus)
– Examples: DB2, SQL Server, Oracle, DB2
• Personal DBMS
– Designed for smaller, simpler database
applications
– Supports fewer than 100 users
– Examples: Access, dBase, FoxPro, Paradox, R-
Base
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21. Personal Database System
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22. How Does the Knowledge in This
Chapter Help Dee and You?
Helps to:
• Know what a DBMS is and what roles it can play
• Understand the diagram of the role of the DBMS for
her blog
– System is isolated from rest of databases
– Uses MySQL as part of functionality of her application
• Be better able to explain what she wants, and that it is
no threat or exception to Oracle standard
• Maybe avoid hiring a consultant
Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall 5-22

23. Role of DBMS for Dee’s Blog
Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall 5-23

24. Guide: No, Thanks, I’ll Use a
Spreadsheet
• Databases take time to build
• Complicated to operate
– May require use of multiple applications
• Need IS people to create it and keep it
running
• Will share data that you may not want to
expose
• Spreadsheets may be a better option in some
cases
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