Deck 11: Object-Oriented DBMSs-Standards and Systems

Question 1

Discuss the Object Model proposed by the Object Data Management Group.

Answer 1

See Section 28.2.2.

Question 2

Case Study 1 - Cornucopia Ltd
Cornucopia Ltd is a large, multinational oil company that uses contractors for systems analysis whenever possible. The following data is held about the contracts:
(a) Each contract consists of a contract name and contract number, the name of the main contracting company, the names of any other companies involved in the contract, the start and scheduled end date for the contract, the budget for the contract and the name of the project manager for the contact.
(b) Each contract consists of a number of tasks, each with an activity name, a start and scheduled end date, a task leader, a work group and a set of deliverables.
(c) A work group consists of a group code and a list of staff. A group leader is identified for each group.
(d) Deliverables take the form of documents, consisting of a document code, a document title, the names of the authors, a list of people the document is to be distributed to, an issue date and the name of the person who has approved the document. Documents come in two forms: requirements specifications and functional specifications.
(e) Company data consists of the name of the company, the technical head of staff, the administrative head of staff, the company's main address (street, city, town, and postcode), a telephone, and fax number.
(f) Each company is divided into a number of divisions, consisting of an address (street, city, town, and postcode), and a divisional head of staff.
(g) Staff data consists of a name, address, and a job title, which determines the hourly cost for the member of staff.
-Using the Object Definition Language (ODL) of the ODMG object model, define the interface of the object schema's types for this case study. For each type, define at least one method that you consider appropriate. State any assumptions necessary to support your design.

Answer 2

See schema diagram on following page for possible solution. Specification for the Project class shown below.

class Project {
(extent projects key projectName)
attribute string projectName;
attribute date startDate;
attribute date scheduledEndDate;
attribute float budget;
relationship Company IsMainContractor inverse Company::HasMainContract;
relationship set IsContractingCompany inverse Company::HasContract;
relationship set ConsistsOf inverse Task::PartOf;
relationship Person Manages inverse Person::ManagerFor;
/* Define operations */
...}

Question 3

Case Study 1 - Cornucopia Ltd
Cornucopia Ltd is a large, multinational oil company that uses contractors for systems analysis whenever possible. The following data is held about the contracts:
(a) Each contract consists of a contract name and contract number, the name of the main contracting company, the names of any other companies involved in the contract, the start and scheduled end date for the contract, the budget for the contract and the name of the project manager for the contact.
(b) Each contract consists of a number of tasks, each with an activity name, a start and scheduled end date, a task leader, a work group and a set of deliverables.
(c) A work group consists of a group code and a list of staff. A group leader is identified for each group.
(d) Deliverables take the form of documents, consisting of a document code, a document title, the names of the authors, a list of people the document is to be distributed to, an issue date and the name of the person who has approved the document. Documents come in two forms: requirements specifications and functional specifications.
(e) Company data consists of the name of the company, the technical head of staff, the administrative head of staff, the company's main address (street, city, town, and postcode), a telephone, and fax number.
(f) Each company is divided into a number of divisions, consisting of an address (street, city, town, and postcode), and a divisional head of staff.
(g) Staff data consists of a name, address, and a job title, which determines the hourly cost for the member of staff.
-Write the following query in the Object Query Language (OQL) of the ODMG object model: 'List the names of all documents delivered under the project named "SCCS".'

Answer 3

SELECT title:x.title
FROM z IN Project,
y IN z.ConsistsOf,
x IN y.HasDeliverables
WHERE z.projectName = 'SCCS'

Question 4

Case Study 2 - Perilous Printing
Perilous Printing Ltd is a small printing company that does work for book publishers. Its jobs consist of printing books or parts of books. The following data is held about the work:
(a) The company does work for many different publishing houses. The data on each publisher consists of a name, an address (street, town, city, and postcode), a telephone, and fax number.
(b) Each printing job consists of a due date, a description and a job type (rush job, normal job, or fill-in). Each printing job is associated with one or more members of staff.
(c) A printing job requires the use of several materials, such as paper and ink. The company holds details of the amount of stock of each type of material that they have on hand together with the price and a reorder level.
(d) Materials are assigned to a job via purchase orders. Each printing job may have several purchase orders assigned to it. Purchase orders identify a vendor and a date for the purchase.
(e) Likewise, each purchase order may contain several purchase order items, containing the quantity of material required.
(f) Company data consists of the name of the company, the technical head of staff, the administrative head of staff, the company's main address (street, town, city, and postcode), a telephone and fax number.
(g) Staff data consists of a name (first and last name), address, and a job title.
-Using the Object Definition Language (ODL) of the ODMG object model, define the interface of the object schema's types for this case study. For each type, define at least one method that you consider appropriate. State any assumptions necessary to support your design.

Question 5

Case Study 2 - Perilous Printing
Perilous Printing Ltd is a small printing company that does work for book publishers. Its jobs consist of printing books or parts of books. The following data is held about the work:
(a) The company does work for many different publishing houses. The data on each publisher consists of a name, an address (street, town, city, and postcode), a telephone, and fax number.
(b) Each printing job consists of a due date, a description and a job type (rush job, normal job, or fill-in). Each printing job is associated with one or more members of staff.
(c) A printing job requires the use of several materials, such as paper and ink. The company holds details of the amount of stock of each type of material that they have on hand together with the price and a reorder level.
(d) Materials are assigned to a job via purchase orders. Each printing job may have several purchase orders assigned to it. Purchase orders identify a vendor and a date for the purchase.
(e) Likewise, each purchase order may contain several purchase order items, containing the quantity of material required.
(f) Company data consists of the name of the company, the technical head of staff, the administrative head of staff, the company's main address (street, town, city, and postcode), a telephone and fax number.
(g) Staff data consists of a name (first and last name), address, and a job title.
-Write the following query in the Object Query Language (OQL) of the ODMG object model: 'List the surnames of all people associated with printing jobs for Addison Wesley Longman.'

Question 6

Case Study 3 - Perfect Pets
A practice called Perfect Pets provides private health care for domestic pets throughout America. This service is provided through various clinics located in the main cities of America. The Director has provided the following description of the current system.
Perfect Pets has many veterinary clinics located in the main cities of America. The details of each clinic include the clinic number, clinic address (consisting of the street, city, state, and zipcode), and the telephone and fax numbers. Each clinic has a Manager and a number of staff (for example, vets, nurses, secretaries, cleaners). The clinic number is unique throughout the practice.
The details stored on each member of staff include the staff number, name (first and last), address (street, city, state, and zipcode), telephone number, date of birth, sex, social security number (SSN), position, and current annual salary. The staff number is unique throughout the practice.
When a pet owner first contacts a clinic of Perfect Pets the details of the pet owner are recorded, which include an owner number, owner name (first name and last name), address (street, city, state, and zipcode), and home telephone number. The owner number is unique to a particular clinic.
The details of the pet requiring treatment are noted, which include a pet number, pet name, type of pet, description, date of birth (if unknown, an approximate date is recorded), date registered at clinic, current status (alive/deceased), and the details of the pet owner. The pet number is unique to a particular clinic.
When a sick pet is brought to a clinic, the vet on duty examines the pet. The details of each examination are recorded and include an examination number, the date and time of the examination, the name of the vet, the pet number, pet name, and type of pet, and a full description of the examination results. The examination number is unique to a particular clinic. As a result of the examination, the vet may propose treatment(s) for the pet.
Perfect Pets provides various treatments for all types of pets. These treatments are provided at a standard rate across all clinics. The details of each treatment include a treatment number, a full description of the treatment, and the cost to the pet owner. For example, treatments include:
T123 $\quad$ Penicillin antibiotic course $\quad$ $50.00
T155 $\quad$ Feline hysterectomy $\quad$ $200.00
T112 $\quad$ Vaccination course against feline flu $\quad$ $70.00
A standard rate of $20.00 is charged for each examination, which is recorded as a type of treatment. The treatment number uniquely identifies each type of treatment and is used by all Perfect Pets clinics.
Based on the results of the examination of a sick pet, the vet may propose one or more types of treatment. For each type of treatment, the information recorded includes the examination number and date, the pet number, name and type, treatment number, description, quantity of each type of treatment, and date the treatment is to begin and end. Any additional comments on the provision of each type of treatment are also recorded.
-Using the Object Definition Language (ODL) of the ODMG object model, define the interface of the object schema's types for this case study. For each type, define at least one method that you consider appropriate. State any assumptions necessary to support your design.

Question 7

Case Study 3 - Perfect Pets
A practice called Perfect Pets provides private health care for domestic pets throughout America. This service is provided through various clinics located in the main cities of America. The Director has provided the following description of the current system.
Perfect Pets has many veterinary clinics located in the main cities of America. The details of each clinic include the clinic number, clinic address (consisting of the street, city, state, and zipcode), and the telephone and fax numbers. Each clinic has a Manager and a number of staff (for example, vets, nurses, secretaries, cleaners). The clinic number is unique throughout the practice.
The details stored on each member of staff include the staff number, name (first and last), address (street, city, state, and zipcode), telephone number, date of birth, sex, social security number (SSN), position, and current annual salary. The staff number is unique throughout the practice.
When a pet owner first contacts a clinic of Perfect Pets the details of the pet owner are recorded, which include an owner number, owner name (first name and last name), address (street, city, state, and zipcode), and home telephone number. The owner number is unique to a particular clinic.
The details of the pet requiring treatment are noted, which include a pet number, pet name, type of pet, description, date of birth (if unknown, an approximate date is recorded), date registered at clinic, current status (alive/deceased), and the details of the pet owner. The pet number is unique to a particular clinic.
When a sick pet is brought to a clinic, the vet on duty examines the pet. The details of each examination are recorded and include an examination number, the date and time of the examination, the name of the vet, the pet number, pet name, and type of pet, and a full description of the examination results. The examination number is unique to a particular clinic. As a result of the examination, the vet may propose treatment(s) for the pet.
Perfect Pets provides various treatments for all types of pets. These treatments are provided at a standard rate across all clinics. The details of each treatment include a treatment number, a full description of the treatment, and the cost to the pet owner. For example, treatments include:
T123 $\quad$ Penicillin antibiotic course $\quad$ $50.00
T155 $\quad$ Feline hysterectomy $\quad$ $200.00
T112 $\quad$ Vaccination course against feline flu $\quad$ $70.00
A standard rate of $20.00 is charged for each examination, which is recorded as a type of treatment. The treatment number uniquely identifies each type of treatment and is used by all Perfect Pets clinics.
Based on the results of the examination of a sick pet, the vet may propose one or more types of treatment. For each type of treatment, the information recorded includes the examination number and date, the pet number, name and type, treatment number, description, quantity of each type of treatment, and date the treatment is to begin and end. Any additional comments on the provision of each type of treatment are also recorded.
-Write the following query in the Object Query Language (OQL) of the ODMG object model: List the names of all pets that received the T123 treatment.