IST459 Spring 2010 - Assignment 2 Case Study

IST459 SPRING 2010 - ASSIGNMENT 2 CASE STUDY

OVERVIEW You are employed as a project analyst at the famous IT consulting firm DataMastersCo Consulting. Your (now former) co-worker, Dudley Doitwrong has messed up another client’s database. It is up to you to fix Dudley’s mistakes and make the client happy once again. Your company’s requirements team as gathered a very accurate set of requirements, so that’s not the issue. The problem is with Dudley’s implementation of those requirements. Being the lazy guy that he is, he skipped the conceptual and logical modeling and went straight to the SQL implementation! Yikes!

WHAT YOU MUST DO Your objective is to improve upon Dudley’s design by using the data modeling tools, data normalization and techniques we learned in class. You will take two separate approaches to correct this problem. In the first approach you will build a logical model from the conceptual model of the requirements. In the second approach you will normalize Dudley’s implementation to produce a logical model in 3NF. When you have both models, you’ll use your expertise to combine the two logical models into the one you’d prefer to implement, and then implement the model in SQL and write scripts to migrate the data. When you’re done you’ll have a new and improved SQL implementation with all the original data intact. Your effort will be divided into 6 graded parts (details are located in the assignment document): 1. Build a conceptual data design based on the requirements collected information and sample data given. This design should be independent of Dudley’s work. 2. Convert your conceptual data design into a logical data design by following the mapping rules we learned in class. 3. Normalize the data in Dudley’s SQL implementation into a logical data design. 4. Decide on the “best” model to use for the new design. Rebuild the internal data model in SQL using the new logical design. 5. Write an SQL script to migrate data from the existing system into the new internal data model / SQL implementation from part 4. NOTE: Since Dudley’s design is so poor there’ bad data. Plan on doing some cleansing. 6. Pack all of your work (diagram / SQL scripts, etc) to a zip file and upload it to the LMS.

THE CLIENT

OVERVIEW Movies4Rent.com is a new addition to the DataMastersCo Consulting family and right now because of what has been deemed the “Dudley situation” they’re not happy customers. Movies4Rent.com is a new internet startup which provides movies rental services only to Bikers (yeah I know, but everyone needs an angle nowadays…haha). Movies4Rent.com (M4R) has contracted with DataMastersCo Consulting to build a system to manage movie rentals for their customers. The data requirements of this system are outlined in the requirements section below.

REQUIREMENTS The business model M4R is quite simple:  Customers sign up for accounts to become members which allow them to rent movies.  Customers must provide basic contact information such as name, address and phone in order to become members.  Any member can rent movies and return rented movies.  Detailed information about each movie should be centralized, a movie can have several copies and the store should keep track of the status of each of those copies. A movie is either RENTED or AVAILABLE  There should be 3 copies for each movie of the movie titles in Dudley's implementation.  Movies must be rated as one of these: G or PG or R or NC17 or NR  Movies must be categorized DRAMA or COMEDY or ACTION or CHILD or SCIFI or DOCUMENTARY  Dues dates for rentals are 7 days from the rental date. Page 1  First name and last name should be independent.  There should be case consistency.

DUDLEY’S SQL IMPLEMENTATION Dudley’s SQL implementation is displayed in the table below. Run the SQL script against your IST-S-STUDENTS SQL database to create Dudley’s implementation. For each of these movies rented there is also an extra copy available for rent.