case mis ch05
TRANSCRIPT
5장
Database Processing
• 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
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This Could Happen to You
• 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
Q1: What Is the Purpose of a
Database?
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• 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.
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Q2: What Does a Database Contain?
Student Table (also called a file)
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• 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
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Relationships Among Records
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Example of Relationships
Among Rows
Figure 5-6
• 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
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Metadata
• 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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Q3: What Is a DBMS and
What Does It Do?
Components of a Database
Application System
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• 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
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Database Management Systems
Creating the Database and Its Structure
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• 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)
Processing the Database
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• 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
Administering the Database
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• Collection of forms, reports, queries, and
application programs that process a database
• Databases can have multiple applications
• Applications can have multiple users
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Q4: What Is a Database Application?
Use of Multiple Database Applications
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• 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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Forms, Reports, and Queries
• 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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Database Application Programs
Example of a Query
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• 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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Q5: What Is the Difference Between an
Enterprise DBMS and a Personal DBMS?
Personal Database System
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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
5-22 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall
How Does the Knowledge in This
Chapter Help Dee and You?
5-23 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall
Role of DBMS for Dee’s Blog
• 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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Guide: No, Thanks, I’ll Use a
Spreadsheet