Mis582 week 6 discussion (dq1+dq2) latest 2017
Mis582 week 6 discussion (dq1+dq2) latest 2017
Subject: General Questions / General General Questions
Question
Week 6 discussion
DQ1
Database Constraints
Business requirements are enforced by implementing database constraints on tables and columns. The database constraints available include the following.
PRIMARY KEY
FOREIGN KEY or REFERENTIAL INTEGRITY
NOT NULL
UNIQUE
CHECK
Give a business requirement and the constraint that could be implemented to enforce it. Explain the constraint you chose, and give the SQL to implement the constraint in the database.
What are the long-term problems when these constraints are not implemented?
DQ2
Database Redesign
After your database was put into production, a design flaw was discovered! One of the relationships modeled as a 1:N relationship was really an N:M relationship. The database issue involves the following tables, with PK italicized and underlined.
VEHICLE (VIN, Make, Model, Color, LicenseTag)
DRIVERS (DriverLicenseNo, LastName, FirstName, Address, Zip, VIN)
ZIPCODE (Zipcode, City, State)
Which 1:N relationship should be an N:M relationship? How would you redesign the database to correct the issue? What else must you consider when updating the structure of your database tables?
