OBJECT-ORIENTED DATABASE APPLICATION DEVELOPMENT


This describes a course taught from Object Database Development: Concepts and Principles, which is aimed at helping students understand how to develop an application using an advanced database system (an object-relational database system, an object-oriented database system, or an active database system). It provides a suggested course description (including prerequisites, objectives, and a discussion of what can be expected), a possible schedule, a set of supporting overhead transparencies, suggested homework assignments, and a suggested sample project.

[Course Description] [Schedule] [Transparency Masters] [Homework Assignments] [Sample Project]


Course Description


Schedule

This suggested schedule is for a 3-hour semester class which meets for 75 minutes twice a week. Sufficient time has been allotted for exams and more in-depth discussion at the discretion of the instructor. A asterisk (*) denotes review material and transparencies from the
relational database course. If students have not taken this course, additional time may be needed and additional material from that course may need to be covered.


Topic Reading Transparencies Assignment Due
Introduction 1 1: 1-5  
OSM 4.1 4: 1-9 *  
OSM 4.2 4: 1-12  
OSM 4.3-5 4: 13-23 Homework 1
Analysis 7.1-2 7: 1-11 Homework 2
Specification 8.1 8: 1-11 Homework 3
OSM-L 8.2 8: 12-21  
Behavior Specification 8.3-5 8: 22-29 Project (Analysis)
Hypergraphs and Red. Transformations 9.1-3,5-6 9: 1-5,32-40 * Homework 4
More Reduction Transformations 9.7-10 9: 42-54 * Homework 5
Flat Scheme Design 10.1,4-5 10: 13-23 * Homework 6
Nested Scheme Design 10.8-10 10: 1-8 Homework 7
Object Modules 11.1 11: 1-5  
Methods & Types 11.2-4 11: 6-15 Project (Specification)
State-Net Transformations 11.5.1 11: 16-24 Homework 8
State-Net Transformations 11.5.2-4 11: 25-29  
Views & Inheritance 11.6-9 11: 30-39 Project (Data Design)
Implementation (ODMG) 12.1-3 12: 1-11 Homework 9
Implementation (ODMG C++) 12.4 12: 12-17 Homework 10
Dev. Methodology (Case Studies) 12.5-6, 14-17 12: 18  
Theoretical Foundation 5.2.1, 6.1-2   Project (Object-Module Design)
Integration Tools 7.3 7: 12-17  
Validation Tools 7.4-5 7: 18-31 Homework 12
Interface Generation Tools 8.4   Homework 13
Reduction Tools -- Semantic Eq. 9.4.2, 9.5-7    
Reduction Tools -- Semantic Eq. 9.8-10    
Synthesis Tools 10.6   Project (Implementation)
Reports & Review     Project (Documentation)


Transparency Masters


Homework Assignments

Homework  1:  1.1, 1.2, 1.3, 1.4, and 1.5.
              (Just make lists for discussion.)

Homework  2:  4.7, 4.8, 4.9, 4.10, 4.11 (use Allegro to do 4.11).
              (Note: additional problems should be assigned for
              students who have not taken the relational database
              course from the book.)

Homework  3:  4.12, 4.15, 4.16, 4.18.

Homework  4:  7.1, 8.1, 8.2.

Homework  5:  8.4, 8.5, 8.7, 8.8.

Homework  6:  8.9, 8.10, 8.11, 8.12.

Homework  7:  8.14, 8.17, 8.18, 8.19.

Homework  8:  9.24, 9.47, 10.33, 10.37.
              (Note: additional problems should be assigned for
              students who have not taken the relational database
              course from the book.)

Homework  9:  11.4, 11.5, 11.6, 11.8, 11.10.

Homework 10:  11.16, 11.17, 11.18.

Homework 11:  11.19, 11.20, 11.21, 11.22, 11.24.

Homework 12:  7.2, 7.3, 7.4b-f, 7.5.

Homework 13:  7.13, 7.14, 7.15, 7.16, 7.17.

Sample Project

``A Personal Travel Agent''

Context and Motivation

Many people would like to have a personal travel agent. Can we provide an automated, individually-tailored agent who knows the desires of its client and adjusts as those desires change and who functions on behalf of its client to provide information, make reservations, and purchase tickets needed for a trip? Can we also enable this agent to glean information from the web and adjust its understanding of the travel world as new information becomes available?

More down-to-earth, can we do some interesting subpart of this problem? Can we create a personal travel agent for helping a client plan a single trip? Suppose we give the agent an ORM application model that describes how a client would like to see the world of travel and hand populate this application model with made-up data as if we had gleaned it from multiple sites on the web. Further suppose that we give the agent a state net representing the workflow that describes how the client would like to interact with the agent and how the agent interacts with the ORM application model. For the sake of making this workflow a little more concrete, let's further suppose that the trip is a business trip and thus that a travel-request form (see below) needs to be filled out and routed and that a cash advance may also be requested and received.


                       TRAVEL APPLICATION FORM

FORM ID# __________             DESTINATION ____________________

NAME ____________________       DEPARTMENT ____________________

DEPARTURE DATE __________       RETURN DATE __________

EXPENDITURES:       ESTIMATED COSTS          REQUESTED ADVANCE

AIR FARE            _______________          N/A

LODGING             _______________          _________________

MEALS               _______________          _________________

          TOTALS:   _______________          _________________


APPROVAL SIGNATURES:

DEPARTMENT CHAIR _____________________

DIRECTOR _____________________

Objectives

  1. Develop a small OSM application model for a specialized personal travel agent to aid in planning and receiving approval for a business trip.
  2. Use the OSM development methodology to transform this application model into an OODBMS implementation.
  3. Observe the development process and make adjustments as necessary so that analysis, specification, design, and implementation documents all reflect the same application definition and provide a smooth transition from analysis through implementation.

Analysis

Use the techniques discussed in the first part of Chapter 7 to do an analysis as follows.
  1. Become familiar with the application. Visit some web sites for airlines and hotels. Look over the travel-application form above.
  2. Use Allegro to create an ORM diagram that describes the essential features of airlines, hotels, and travel applications. Be sure to include (1) available flights, (2) available rooms at hotels, (3) specific flight and hotel reservations, when held/made, (4) estimated costs and totals, (5) cash advance costs and totals, and (6) basic information on the form.
  3. Use Allegro to develop OBM/OIM diagrams for determining and booking flights and hotel reservations and for processing a travel application. Give your client a choice among a small number of alternative flights and hotel/room selections. Get these choices from your database of all possibilities. Have your travel-application agent get basic information from your client, get flight and hotel information from your airline and hotel agent and present it to your client for making final selections, instruct flight agents to book flights and hotel agents to book rooms, compute totals for estimates and advance amounts, and route the information as needed to obtain signatures. If the trip is denied, cancel flights and hotel reservations. If the trip is approved, store final information -- flights, hotel reservations, and travel-application form information so that it can be displayed on demand.

Specification

Use the techniques discussed in Chapter 8 to do a specification as follows.
  1. Rework your ORM model instance as may be necessary.
  2. Add a system boundary to your ORM model instance. (You may put this on the diagram by hand.)
  3. Write the ORM model instance within your system boundary in OSM-L. Use the latest OSM-L grammar, and check your OSM-L code by executing the OSM-L parser.
  4. Rework your OBM/OIM model instances as may be necessary.
  5. Use OSM-L to give a fully formal OBM/OIM for your hotel agent. Check your OSM-L code by executing the OSM-L parser.
  6. Use mixed OSM-L and graphical notation to give a fully formal specification for your airline agent. The graphical notation should retain the basic flow of activities. Use Allegro to provide this specification.
  7. Partially formalize your travel-application agent. The partial formalization should graphically show the basic flow of activities. The triggers and actions may be informal, but should contain enough explanation/formalism that a person (other than yourself) could code your specification without having to return to you for further clarification. Use Allegro to provide this specification.
  8. Use interface forms to fully formalize client input to the travel-application agent. (Other interfaces need not be formalized with interface forms.)

Data Design

Use the techniques in Chapters 9 and 10 to convert the data part of your ORM diagram that falls within the implementation boundary as follows.

  1. Produce a flat relational database scheme that has no potential redundancy and no potential nulls. Include a specification of the inclusion dependencies and keys.
  2. Produce a nested relational database scheme in NNF. Select good roots for your scheme trees.
  3. Do any needed basic structural adjustments to your NNF schemes, so that they will be cost effective for your application. Justify any adjustments you make. (Adjustments for computed relationship sets and data structures come later.)

Object-Module Design

Use the techniques in Chapter 11 to convert your specification into a design as follows.

  1. Adjust your cost-effective NNF schemes by adding methods for any computed relationships such as total estimated cost and total advance requested. Add types, including bulk types such as arrays and lists where appropriate. (You may rework your initial ORM diagrams based on what you've learned and on the feedback you've received.)
  2. Transform every state net to a zero-state state net. Add transaction processing where appropriate. (You may rework your initial OBM diagrams based on what you've learned and on the feedback you've received.)
  3. Specify object modules for your design. Integrate your data and behavior designs by creating object modules that appropriately contain both data and behavior. That is, data for the airline agent should be with the behavior of the airline agent, and so forth, for the other agents. If appropriate, properly designate visibility, views, and inheritance.

Implementation

Implement your design. Translate your object modules into the syntax of a target OODBMS (the correspondence must be clear). Provide "ad hoc" queries to display hotel and airline reservations and stored travel-application information.

Documentation

Make adjustments to your analysis, specification, design, and implementation as may be necessary so that everything works smoothly together and corresponds as it should. This becomes your final documentation for your project. Also, write comments (a page or so) about the development process. Answer questions such as what worked well, what worked poorly, and why.