Assignment 7
Due date: Friday, Dec. 4, 11:59PM.
NOTES:
- Start early!
- This is an individual assignment; no groups allowed.
This assignment is meant to give you practice with Relational Algebra, refresh your SQL, and Transactions.
Problem 1
Solve Exercise 6.11 a), b), c), and d) in the textbook. Give the SQL queries 6.11 a), b), c), and d), as well.
Problem 2
Solve Exercise 6.14 a) and b) (this one is a bit tricky). Give the SQL queries 6.11 a), b), c), and d), as well.
Problem 3:
Consider the following classes of schedules: serializable and conflict serializable. For each of the
following schedules, state which of the preceding classes it belongs to. If you cannot decide whether a schedule belongs in a certain class, explain briefly.
- T1:R(X), T2:R(X), T1:W(X), T2:W(X).
- T1:W(X), T2:R(Y), T1:R(Y), T2:R(X).
- T1:R(X), T2:R(Y), T3:W(X), T2:R(X), T1:R(Y).
- T1:R(X), T1:R(Y), T1:W(X), T2:R(Y), T3:W(Y), T1:W(X), T2:R(Y).
Deliverables
- a document with the solutions to the above problems.
Upload the document in blackboard.