CP5633 Database Modelling
Assignment 1- ERD Modelling
Assignment worth: 15%
Due date: Thursday, 17th of August 2018 @5pm
Note: This is an individual assignment. While it is expected that students will discuss their ideas with one another, students need to be aware of their responsibilities in ensuring that they do not deliberately or inadvertently plagiarize the work of others.
This assignment has been designed to assess students’ ability to model data, by constructing an entity-relationship diagram for a particular business scenario. This assignment addresses the following learning objectives for this subject:
- Perform conceptual modelling using Entity-Relationship Diagrams (ERDs)
- Discuss business assumptions which affect data modelling. Model a database using the entity-relationship (ER) model and understand the database development process
- Use the techniques of normalization
- You are to write a brief discussion of your solution, i.e. how you approached the modelling problem and any issues you may have encountered (maximum of ½ page).
- You are to write all applicable business rules necessary to establish entities, relationships, optionalities, connectivities, cardinalities and constraints. If a many–to-many relationship is involved, state the business rules regarding the bridging entities after breaking down the many-to-many relationship. An example business rules format can be found in Appendix A of this document. Business rules you write are expected to be in the same format as presented in Appendix A.
- Based on these business rules,* draw a fully labelled and implementable Entity-Relationship Diagram (ERD). Include all entities, relationships, optionalities, connectivities, cardinalities and constraints. You must use Crow’s foot notation and MS Visio to create the ERD (a hand-drawn ERD will NOT be accepted). A sample ERD can be found in Appendix A of this document. (Note: The ERD created using Visio will need to be saved as an image file and then be included in your document file to be submitted).
- A summary to describe the major justifications, assumptions and limitations related to your database design. For example:
- Assumption/justifications for optionalitiy, connectivities, constraints data type and data domain; and
- Special cases or data integrity issues that cannot be handled.
Note: Designing the database is an iterative process; you may find yourself going back and forth between Tasks 1 and 3 to revise the design. Make sure that your final submission shows consistent design in the business rules and ERD.
- You need to submit a document file (MS Word format) to LearnJCU; this document should include all the answers for tasks 1-4. Please name the file as doc.
- You need to submit the MS Visio file containing the ERD.
- Timestamp shown on LearnJCU assignment submission will be used to determine if the assignment is late or not. Refer to the subject guide for the policy for late submission.
The Amazing_Charter Company operates a fleet of aircraft under the Federal Air Regulations Part 135 certificate (FAR 135). The aircraft are available for air taxi (charter) operations within the United States and Canada.
Charter companies provide so-called “unscheduled” operations—that is, charter flights take place only after a customer reserves the use of an aircraft to fly at a customer-designated date and time to one or more customer-designated destinations, transporting passengers, cargo, or some combination of passengers and cargo. A customer can, of course, reserve many different charter flights (trips) during any time frame. However, for billing purposes, each charter trip is reserved by one and only one customer.
Each charter trip yields revenue for the Amazing_Charter Company. That revenue is generated by the charges that a customer pays upon the completion of a flight. The charter flight charges are a function of aircraft model used, distance flown, waiting time, special customer requirements and crew expenses. The distance flown charges are computed by multiplying the round-trip miles by the model’s charge per mile. Round-trip miles are based on the actual navigational path flown. The sample route traced in Figure 1 illustrates the procedure. Note that the number of round-trip miles is calculated to be 130 + 200 + 180 + 390 = 900.
Figure 1: Round-trip mile determination.
Depending on whether a customer has Amazing_Charter credit authorization, the customer may:
- Pay the entire charter bill upon the completion of the charter flight.
- Pay a part of the charter bill and charge the remainder to the account. The charge amount may not exceed the available credit.
- Charge the entire charter bill to the account. The charge amount may not exceed the available credit.
Customers may pay all or part of the existing balance for previous charter trips. Such payments may be made at any time and are not necessarily tied to a specific charter trip. The charter mileage charge includes the expense of the pilot(s) and other crew required by FAR 135. However, if customers request additional crew not required by FAR 135, those customers are charged for the crew members on an hourly basis. The hourly crew-member charge is based on each crew member’s qualifications.
The database must be able to handle crew assignment. Each charter trip requires the use of an aircraft, and a crew flies each aircraft. The smaller piston engine-powered charter aircraft require a crew consisting of only a single pilot. Larger aircraft (that is, aircraft having a gross take-off weight of 12,500 pounds or more) and jet-powered aircraft require a pilot and a co-pilot, while some of the larger aircraft used to transport passengers may require flight attendants as part of the crew. Some of the older aircraft require the assignment of a flight engineer, and larger cargo-carrying aircraft require the assignment of a loadmaster. In short, a crew can consist of more than one person and not all crew members are pilots.
The charter flight’s aircraft waiting charges are computed by multiplying the hours waited by the model’s hourly waiting charge. Crew expenses are limited to meals, lodging, and ground transportation.
The Amazing_Charter database must be designed to generate a monthly summary of all charter trips, expenses, and revenues derived from the charter records. Such records are based on the data that each pilot in command is required to record for each charter trip: trip date(s) and time(s), destination(s), aircraft number, pilot (and other crew) data, distance flown, fuel usage, and other data pertinent to the charter flight. Such charter data are then used to generate monthly reports that detail revenue and operating cost information for customers, aircraft, and pilots. All pilots and other crew members are Amazing_Charter Company employees; that is, the company does not use contract pilots and crew.
FAR 135 operations are conducted under a strict set of requirements that govern the licensing and training of crew members. For example, pilots must have earned either a Commercial license or an Airline Transport Pilot (ATP) license. Both licenses require appropriate ratings. Ratings are specific competency requirements. For example:
- To operate a multiengine aircraft designed for take-offs and landings on land only, the appropriate rating is MEL, or Multiengine Landplane. When a multiengine aircraft can take off and land on water, the appropriate rating is MES, or Multiengine Seaplane.
- The instrument rating is based on a demonstrated ability to conduct all flight operations with sole reference to cockpit instrumentation. The instrument rating is required to operate an aircraft under Instrument Meteorological Conditions (IMC), and all such operations are governed under FAR-specified Instrument Flight Rules (IFR). In contrast, operations conducted under “good weather” or visual flight conditions are based on the FAR Visual Flight Rules (VFR).
- The type rating is required for all aircraft with a take-off weight of more than 12,500 pounds or for aircraft that are purely jet-powered. If an aircraft uses jet engines to drive propellers, that aircraft is said to be turboprop-powered. A turboprop—that is, a turbo propeller-powered aircraft—does not require a type rating unless it meets the 12,500-pound weight limitation.
Although pilot licenses and ratings are not time-limited, exercising the privilege of the license and ratings under Part 135 requires both a current medical certificate and a current Part 135 checkride. The following distinctions are important:
- The medical certificate may be Class I or Class II. The Class I medical is more stringent than the Class II, and it must be renewed every six months. The Class II medical must be renewed yearly. If the Class I medical is not renewed during the six-month period, it automatically reverts to a Class II certificate. If the Class II medical is not renewed within the specified period, it automatically reverts to a Class III medical, which is not valid for commercial flight operations.
- A Part 135 checkride is a practical flight examination that must be successfully completed every six months. The checkride includes all flight manoeuvres and procedures specified in Part 135.
Non-pilot crew members must also have the proper certificates in order to meet specific job requirements. For example, loadmasters need an appropriate certificate, as do flight attendants. In addition, crew members such as loadmasters and flight attendants, who may be required in operations that involve large aircraft (more than a 12,500-pound take-off weight and passenger configurations over 19) are also required periodically to pass a written and practical exam. The Amazing_Charter Company is required to keep a complete record of all test types, dates, and results for each crew member, as well as pilot medical certificate examination dates.
In addition, all flight crew members are required to submit to periodic drug testing; the results must be tracked, too. (Note that nonpilot crew members are not required to take pilot-specific tests such as Part 135 checkrides; nor are pilots required to take crew tests such as loadmaster and flight attendant practical exams.) However, many crew members have licenses and/or certifications in several areas. For example, a pilot may have an ATP and a loadmaster certificate. If that pilot is assigned to be a loadmaster on a given charter flight, the loadmaster certificate is required. Similarly, a flight attendant may have earned a commercial pilot’s license. Sample data formats are shown in tables below.
SAMPLE DATA FORMATS
Part A Tests
|TEST CODE||TEST DESCRIPTION||TEST FREQUENCY|
|1||Part 135 Flight Check||6 months|
|2||Medical, Class 1||6 months|
|3||Medical, Class 2||12 months|
|4||Loadmaster Practical||12 months|
|5||Flight Attendant Practical||12 months|
|7||Operations, written exam||6 months|
Part B Results
|EMPLOYEE||TEST CODE||TEST DATE||TEST RESULT|
Part C Licenses and Certificates
|LICENSE OR CERTIFICATE||LICENSE OR CERTIFICATE DESCRIPTION|
|ATP||Airline Transport Pilot|
|Med-1||Medical certificate, class 1|
|Med-2||Medical certificate, class 2|
|MEL||Multiengine Land aircraft rating|
Part D Licenses and Certificates Held by Employees
|EMPLOYEE||LICENSE OR CERTIFICATE||DATE EARNED|
Pilots and other crew members must receive recurrency training appropriate to their work assignments. Recurrency training is based on an FAA-approved curriculum that is job-specific. For example, pilot recurrency training includes a review of all applicable Part 135 flight rules and regulations, weather data interpretation, company flight operations requirements, and specified flight procedures. The Amazing_Charter Company is required to keep a complete record of all recurrency training for each crew member subject to the training.
The Amazing_Charter Company is required to maintain a detailed record of all crew credentials and all training mandated by Part 135. The company must keep a complete record of each requirement and of all compliance data.
To conduct a charter flight, the company must have a properly maintained aircraft available. A pilot who meets all of the FAA’s licensing and currency requirements must fly the aircraft as Pilot in Command (PIC). For those aircraft that are powered by piston engines or turboprops and have a gross take-off weight under 12,500 pounds, single-pilot operations are permitted under Part 135 as long as a properly maintained autopilot is available. However, even if FAR Part 135 permits single-pilot operations, many customers require the presence of a co-pilot who is capable of conducting the flight operations under Part 135.
The Amazing_Charter operations manager anticipates the lease of turbojet-powered aircraft, and those aircraft are required to have a crew consisting of a pilot and co-pilot. Both pilot and co-pilot must meet the same Part 135 licensing, ratings, and training requirements.
The company also leases larger aircraft that exceed the 12,500-pound gross take-off weight. Those aircraft can carry the number of passengers that requires the presence of one or more flight attendants. If those aircraft carry cargo weighing over 12,500 pounds, a loadmaster must be assigned as a crew member to supervise the loading and securing of the cargo.
APPENDIX A: SAMPLE BUSINESS RULES & ERD
Business Rules Examples:
- A customer may request many charter trips.
- Each charter trip is requested by only one customer.
- An employee may be assigned to serve as a crew member on many charter trips.
- Each charter trip may have many employees assigned to it to serve as crew members.
Example ERD Format