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Database Systems
1. List the ACID properties. Explain the usefulness of each.
2. Consider the following two transactions: T13: read(A);read(B);if A = 0 then B := B + 1;write(B).T14: read(B);read(A);if B = 0 then A := A + 1;write(A).Let the consistency requirement be A = 0 or B = 0, with A = 0 and B = 0 as the initial values.a. Show that every serial execution involving these two transactions preserves the consistency of the database.b. Show a concurrent execution of T13 and T14 that produces a nonserializable schedule.c. Is there a concurrent execution of T13 and T14 that produces a serializable schedule?
3. What is the two-phase locking protocol? What is the strict two-phase locking protocol? What is the rigorous two-phase locking protocol? What benefit does strict two-phase locking protocol provide? What benefit does rigorous two-phase locking protocol provide?
4. Consider the log in Figure. Suppose there is a crash just before the <T0 abort> log record is written out. Explain what would happen during recovery.
Explain the role of a database administrator,the tasks performed by this role and why this role is important in Database Management.
Using Join, list the items each customer ordered where the billing_price was lower than the item price (item, billing_price, and price). Sort the results alphabetically by customer name.
Consider system which produces budget reports for department at university. For whichever system you select, answer the following design questions. Who will use output?
Hhow can you change column name or what is a different way to write statement in SQL so it displays the amount column as money.
Create a database for Ray. He is interested in movies and wants to keep information on movies, actors, and directors in a database. The only user is Ray, and he needs to produce reports.
Find the average number of books borrowed per member. Take into account that if a member does not borrow any books, then that member does not appear in the borrowed relation at all.
Design a scheme for determining exactly which one of the wine bottles was poisoned in just one month's time while expending O(logn) taste testers.
Create Entity-Relationship diagram for a bookstore database, that maintains information about books, professional journals, their authors, and publishers.
Using example of vehicles and drivers, explain issues to convert relationship for new cardinality including new relationships and attributes for the tables.
What are triggers used for, and why are they important in database systems? Provide an example of a situation where a trigger would be appropriate.
Describe briefly what are the main benefits of using DBMS to manage data in program applications involving extensive data access.
Using Internet as the research tool for extra information not presented in text, describe why application roles are important part of the security model for databases.
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