INFO 1103 Homework Project 1

Transcription

1 INFO 1103 Homework Project 1 January 22, 2018 Due February 7, at the end of the lecture period. 1 Introduction Many people enjoy dog shows. In this homework, you will focus on modelling the data represented on the CanuckDogs website, com/. We will simplify a little bit, in that we focus only on conformation dog shows. I found a document by a club that defines many of the terms you may see on the CanuckDogs site: it is glossary.htm. 2 More Details The CanuckDogs people have lost the code/design for their database and the person who designed it has been run over by a bus 1. They need your help to redesign it from scratch. Luckily, the system still shows information and you have managed to interview Rex from CanuckDogs about the system. During the interview with Rex, the following facts are discovered. Not all are relevant for the system being designed, and the ERD you are preparing should omit irrelevant things. Rex (and Dr. Kaser) could be wrong about some details, and if there is a conflict between these items and your more official resources, you should go with the more official resources. 1. Although there are several types of dog shows, we focus only on allbreeds conformation shows in our redesign. So you need not worry about obedience or agility shows, and so forth. 2. This database system will be run by W. E. Coyote, and data will be added by B. Bunny and R. Herrink. 3. There are two kinds of points awarded from winning various competitions at a show: Top Dog points given out by this organization according to its own complicated rules, and championship points given out to dogs that 1 Rumour says a Greyhound. 1

2 are working on a Champion of Record status (according to complicated rules laid out by the Canadian Kennel Club). 4. Dogs start out as class dogs and may collect up enough championship points (10) that they can achieve Champion of Record status. Moreover, the points have to have been received from at least 3 different judges. 5. The details of how to compute how many points (Top Dog or championship) are awarded for winning a given competition can be glossed over. If you use a derived attribute, you do not need to supply the exact formula. However, the formula will depend upon how many other dogs are competing in a given competition, so the system will need to have this information. 6. We want to be able to know which dogs will have become Champions of Record based on the points received. 7. We want to know how many TopDog points any specified dog had, at the end of any particular month. (This should be derivable by adding up the TopDog points received to that date.) 8. Certain competition are open only to class dogs and closed to dogs that have become Champions of Record. The opposite is not true. 9. Sometimes, the number of dogs that competed in a given class is specified. It will be given as four numbers, representing the number of males, altered males, females and altered females. The complicated formulas will need this information. Other times the current CanuckDogs website just shows the number of points that the complicated formulas would produce. 10. There are complicated relationships about which dogs can compete in which competitions. For instance, the only class dogs that are allowed to enter the Best-of-Breed competition are the winners of the Winners Dog and Winners Bitch 2 competitions. (Champion of Record dogs are also allowed to compete for Best-of-Breed.) We have decided not to keep track of these complicated relationships in our databases and will rely on the human judges to make sure that ineligible dogs don t compete. However, the judges will rely on our system to tell them which dogs have become Champions of Record or to find the age and breed of a dog. 11. Class dogs are subdivided into specific classes, such as Junior Puppy 3, Novice, Canadian Bred, and so on. A given dog might can belong to several subdivisions: a 7-month-old puppy bred in Saint John is both a Junior Puppy and a Canadian Bred. It will compete against other dogs of its gender status (male, altered male, female, altered female). 2 To dog-show people, bitch is not a dirty word. I ve written this document to mostly refer to female dogs to lessen the shock factor, but you can use the technical term without fear, in a technical dog-show context. 3 I think Junior Puppy is also known as Baby Puppy. 2

3 12. Dogs can also be divided into 7 groups, depending on their breed. For instance, Group 4 consists of terriers. One breed that belongs to Group 4 is Cairn Terrier. There is a fixed set of a few dozen breeds. Your design should not have Cairn Terrier as an entity type, though it would be fine as an entity instance. Dogs have Top Dog ranks computed by this system based on points. A given dog has a rank within its breed, a rank within its group, and a rank within all dogs. Ranks change over time as a dog wins more competitions and as its competitors also win more competitions. 13. There is a fixed set (fairly small) of possible competitions, such as Best Senior Puppy Bitch, Best of Breed, and Best of Winners. Some of these competitions are held separately, in the show, for each breed. Others, such as Best of Group, involve dogs of various breeds that are in the same group. (Best in group has first- through fourth-place awarded. In CanuckDogs this is GP1 to GP4) And there are other competitions that involve dogs of various groups. An example is Best In Show (abbreviated BIS in CanuckDogs). 14. Most dog events extend over several days, and there may be one or more shows on each day (for instance, a Saturday morning show and a Saturday afternoon show). A given dog may compete for Best Senior Puppy Bitch as a Golden Retriever in the Saturday morning and compete again in Saturday evening show, as well as the Sunday evening show. 15. Some judges are qualified to judge only certain groups or breeds. As a result, a given dog show may use several different judges. (However, it seems common for dog shows to use judges who are qualified to judge all breeds, in which case a single judge can handle the entire show.) Notes: We want our system to be able to detect a judge who ends up judging a group or breed for which he is not qualified. You are not assumed to know much about dog shows before you start this assignment. However, when you model a domain, you often need to increase your knowledge of it. Besides the information listed above, you will need to explore the Canuck- Dogs website to see what else you need to capture. You will not need to look into the Marketplace, Classifieds, Advertising,Fundraising or Contact Us tabs. Make sure you click on hyperlinked things like dog names, judge names and so forth, to explore the CanuckDogs website fully. Your model will consist of an ER diagram, as well as metadata in the form of entity, attribute and relationship definitions. 3

4 Use only a basic ER diagram, as discussed in Chapter 2; do not use the extended ER diagrams of Chapter 3. Use multivalued attributes and many-to-many relationships where they make sense. Do not transform them away for the reason we have to get rid of them to produce a relational design. Your solution should have at least one multivalued attribute and one associative entity. Every entity (except weak or associative entities) should have simple or composite unique identifiers. My sample solution, which may not be perfect, has 7 regular entities, 1 associative entity, and two weak entities. Yours does not have to match this, but it may be useful to have some idea of the size of my solution. This homework must be solved individually, not by group work. Do not discuss your assignment, except perhaps in the broadest terms. Items that you could discuss might include the number of attributes, or things that you think are outside the scope of what needs to be modelled. 3 ER Diagram You can either hand-draw your diagram or use the Oracle Data Modeller tool that we used in the lab. 1. If your diagram is hand drawn, use the book s notation. Your diagram does not need to be beautiful, but neither should it be a horrible illegible mess. Using a ruler would be safe but is not necessary for most people. 2. If you use the Oracle Data Modeller tool, use Information Engineering notation and use the Data Modeller s ability to add comments/notes as the way to display information about relationships. Multivalued or composite attributes can be given names that include funny characters such as { and (. To distinguish weak or associative attributes in the diagrams, when using the Data Modeller, you can give the entity a name that includes Assoc or Weak. You should be able to entice the Data Modeller to export your diagram as a PDF. This is to be preferred over a screenshot, which can be harder to read. In either case, you will need the ERD in electronic form so that you can submit it to D2L. For hand-drawn diagrams, your best bet is a scan. A photograph can be used instead of a scan, if it is a good photograph. Any photograph (or scan) that is too hard to read may result in your being asked to submit a high-quality scan so hold on to the original diagram. There are scanners in some ITS labs, and perhaps the photocopiers in the library have this capability. Follow the textbook s guidelines for naming entities, attributes and relations. 4

5 4 Other metadata Produce a document (in PDF) including entity definitions (follow the style on the top half of textbook page 48, plus see guidelines on pages 51, 52 and 56); attribute definitions (following Figure 2-6, augmented with the things discussed on page 61 and 62. ); relationship definitions (follow the guidelines that start toward the end of page 76 and go a little bit into page 78). This document is longer and its creation more tedious than you might expect. If you follow these rules, this document will be at least a few pages long. 5 Submitting Submit your ERD and also your other metadata document as PDFs to D2L. Also submit hard copies, either in class or via the drop-box outside of HH305B. This assignment is due on February 7, at 2:30 p.m. You will probably be assigned a second homework before then. 5