SQL. I have 35 written questions and 5 SQL assignments.I will provide all three Query languages for the database and the ER Diagram. For the SQL assignments, you must provide both the SQL statement
Review Questions 1
Please answer these questions in your own words:
1. What is redundancy? What problems are associated with redundancy?
2. What is an entity? An attribute?
3. What is a relationship? A one-to-many relationship?
4. How do you create a one-to-many relationship in a database system?
5. What is an E-R diagram?
6. What is database design?
7. What is an integrity constraint? When does a database have integrity?
8. What is data independence? Why is it desirable?
9. How can the complexity of a DBMS be a disadvantage?
10. Why can a failure in a database environment be more serious than an error in a non-database environment?
Review Questions 2
Please answer these questions in your own words:
1. What is a relational database?
2. What is an unnormalized relation? Is it a relation according to the definition of the word relation?
3. How is the term attribute used in the relational model? What is a more common name for attribute?
4. What is a primary key? What is the primary key for each table in the Colonial Adventure Tours database shown in the Colonial Tours ER Diagram file?
5. Describe the purpose of the UNION command in relational algebra.
Review Questions 3
Please answer these questions in your own words:
1. Define functional dependence.
2. Define candidate key.
3. Define first normal form.
4. Define second normal form. What types of problems would you find in tables that are not in second normal form?
5. Define third normal form. What types of problems would you find in tables that are not in third normal form?
Review Questions 4
Please answer these questions in your own words:
1. Define the term user view as it applies to database design.
2. The information-level design method presented in this lecture contains steps that must be repeated for each user view. List the steps and briefly describe the kinds of activities that must take place at each step.
3. A database at a college is required to support the following requirements. Complete the information- level design for this set of requirements. Use your own experience to determine any constraints you need that are not stated in the problem. Represent the answer in DBDL.
- For a department, store its number and name.
- For an advisor, store his or her number and name and the number of the department to which he or she is assigned.
- For a course, store its code and description (for example, MTH110 or Algebra).
- For a student, store his or her number and name. For each course the student has taken, store the course code, course description, and grade received. In addition, store the number and name of the student’s advisor. Assume that an advisor may advise any number of students but that each student has just one advisor.
4. List the changes you would need to make in your answer to Question 3 if a student could have more than one advisor.
5. Suppose in addition to the requirements specified in Question 4, you must store the number of the department in which the student is majoring. Indicate the changes this would cause in the design if the student’s advisor does not necessarily have to be in the department in which the student is majoring.
Review Questions 5
Please answer these questions in your own words:
1. What is metadata? Which component of a DBMS maintains meta data?
2. How does a catalog differ from a data dictionary?
3. What is meant by concurrent update?
4. Describe a situation that could cause a lost update.
5. What is locking, and what does it accomplish?
6. Describe two-phase locking.
7. What is deadlock? How does it occur?
8. What is security?
9. What is encryption? How does encryption relate to security?
10. What is authentication? Describe three types of authentication.
