Download Database Application Design - CLAIR

January 7, 2000
Database Application Design
Handout #1
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University of Michigan
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Course information
• Instructor: Dragomir R. Radev
([email protected])
• Office: 305A, WH, Phone: 615-5225
• Office hours: TBD
• Course page:
http://www.si.umich.edu/~radev/654w00/
• Meeting time:
Fridays, 3:00 - 6:00 PM, 311 WH
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University of Michigan
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Books
• Required:
Database Processing by David Kroenke
(7th Edition, Prentice Hall, ISBN 0-13-084816-6)
• Recommended:
MySQL and mSQL by Yarger, Reese, and King
(O'Reilly, ISBN 1-56-592434-7)
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Structure of the course
•
•
•
•
Lectures
Assignments
Final project
Final exam
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Assignments
• Assignment 1: SQL problem set
• Assignment 2: TBD
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Final project
•
•
•
•
•
Proposal
Database design
Progress report
Project
Final presentation
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Grading
• Two assignments: 30% (15% each)
• Project: 40%
• Final exam: 30%
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Policies
• Attendance counts as 10% of the grade
• Timely submission of assignments is
important
• Syllabus can be amended during the
semester
• Honors Code
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Notes on programming
• All students will do some programming as
part of the assignments.
• For the final project, teams will be formed
in ways to include students with diverse
backgrounds.
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Syllabus
• 1. Relational Model
– Relations, Domains, Attributes, Keys, Representation,
Manipulation
– Integrity
– Engines: Oracle, MS Access, Sybase, mSQL, MySQL
• 2. SQL
– Syntax and semantics of SQL
– Queries, subqueries, joins
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Syllabus
• 3. Programming in SQL
– Use of views
– Queries using EXISTS, set comparison queries
– Outer joins
• 4. Database design
– Data modeling
– Conventions
– Design review
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Syllabus
• 5. Application design
– Application structure
– Prototyping
• 6. Web interfaces
– HTML forms
– Dynamic Web pages
– Interface issues
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Syllabus
• 7. mSQL, MySQL, and Oracle
– Availability
– Functionality
– Similarities and Differences
• 8. System administration
– Database administration
– Security
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Readings for next time
• Kroenke
– Chapter 1: Introduction to Database Processing
– Chapter 2: Introduction to Database
Development
• YRK (optional)
– Chapter 1: Introduction to Relational Databases
– Chapter 2: Database design
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University of Michigan
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Introduction to database
processing
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Databases
• Move WWW beyond simple publishing
• Examples:
–
–
–
–
personal : Mary Richards House Painting
workgroup: Treble Clef Music
organizational: DMV licensing and registration
Internet technology: Calvert Island
Reservations
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Type
Personal
Example
Typical # of Typical Size of DB
concurrent
users
Mary Richards 1
< 10 MB
House Painting
< 25
< 100 MB
Organizational Licensing and
Registration
Hundreds
> 1 Trillion Bytes
Calvert Island
Reservations
Possibly
hundreds
Any
Workgroup
Internet
Technology
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University of Michigan
Treble Clef
Music
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More examples
• Give examples of databases which you have
been using for research or entertainment.
• Library of congress
• ACL Universe
• Profile
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Issues
• Databases vs. database applications?
• Forms, reports, queries
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File processing systems (FPS)
Customer
processing
application
Customer
file
Rental
processing
application
Rental
file
Customer file user
Rental file user
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Problems with FPS
• Data are separated and isolated
• Data are often duplicated
• Application programs are dependent on file
formats
• Files are often incompatible with one
another
• It is difficult to represent data in the users’
perspectives
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Separated and isolated data
• Merging files
• Which parts
• Complexity
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Data duplication
• Data integrity
• Updates
• Credibility
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Application program dependency
• Format changes
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Incompatible files
• Cobol vs. Visual Basic vs. C
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Users’ perspectives
• Relationships among records are not easily
represented or processed
• E.g., customer preferences
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Database processing systems
•
•
•
•
Integrated data
Reduced data duplication
Program/data independence
Easier representation of the users’
perspectives
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Definition of a database
• Self-describing: user data + structure data
(metadata or data directory)
• Collection of integrated records, usually
indexed
• DB is a model of the users’ model
• Transactions
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Structure of FPS and DBS
•
•
•
•
•
•
Bytes
Fields
Records
Files
DBS only: Metadata
DBS only: Indexes
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The relational Model
• E.F. Codd, “A Relational Model of Data for
Large Shared Databanks” in CACM, June
1970, pp. 377-387
• Data is stored in tables
• Normalization
• Ashton-Tate, then Borland (dBase II)
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Client-server database
applications
• Shared files
• Multiple CPUs (cf. mainframe)
• Internet technology
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Questions
• Why is database processing an important subject?
• What are the main differences between a single-user and a
multi-user database?
• What are the limitations of file processing systems as
described in the lecture?
• What is a database? Metadata?
• What is the relational model?
• Check out the Web sites of Dell and Amazon. What
databases are involved? Which is the most recent book by
Günter Grass?
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Introduction to database
development
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Example: registrar’s data
• Relations and tuples
• Example: StudentName, StudentPhone,
AdviserName, AdviserPhone
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StudentName
StudentPhone
AdviserName
AdviserPhone
Baker, Rex
232-8897
Parks
236-0098
Charles, Mary
232-0099
Parks
236-0098
Johnson, Beth
232-4487
Jones
236-0110
Scott, Glenn
232-4444
Parks
236-0098
Zylog, Frita
232-5588
Jones
236-0110
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Questions
• What happens if Adviser Parks changes his
phone number?
• What is a possible solution?
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Use two relations: R1 and R2
R1
StudentName
StudentPhone
AdviserName
Baker, Rex
232-8897
Parks
Charles, Mary
232-0099
Parks
Johnson, Beth
232-4487
Jones
Scott, Glenn
232-4444
Parks
Zylog, Frita
232-5588
Jones
R2
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University of Michigan
AdviserName
AdviserPhone
Parks
236-0098
Jones
236-0110
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SysTables table
Table Name
Number of Columns Primary Key
Student
Adviser
Course
Enrollment
4
3
3
3
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University of Michigan
StudentNumber
AdviserName
ReferenceNumber
{StudentNumber,
ReferenceNumber}
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SysColumns table
Column Name
Table Name
Data Type
Length
StudentNumber
FirstName
LastName
Major
AdviserName
Phone
Department
ReferenceNumber
Title
NumberHours
StudentNumber
ReferenceNumber
Grade
Student
Student
Student
Student
Adviser
Adviser
Adviser
Course
Course
Course
Enrollment
Enrollment
Enrollment
Integer
Text
Text
Text
Text
Text
Text
Integer
Text
Decimal
Integer
Integer
Text
4
20
30
10
25
12
15
4
10
4
4
4
2
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CREATE TABLE acllink
(
link_id CHAR(10),
url CHAR(190),
title CHAR(110),
author CHAR(60),
cat1 CHAR(30),
cat2 CHAR(20),
cat3 CHAR(20),
cat4 CHAR(20),
email CHAR(40),
annotation TEXT(50),
date_added TEXT(30),
date_indexed TEXT(30)
)
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