Databases | SQL | Oracle | MS Access Answers

Write a program to create a queue that permits insertion at any vacant location at the rear end.

Q3.A. Consider the relation schema R = (E,F,G,H,I,J,K,L,M,N) And the set of functional dependencies {{E,F} -> {G}, {F} -> {I,J},{E,H} ->{K,L}->{M},{K}->{M},{L}->{N}} on R. Find the key for R?

Q3. B. Consider the schema R(ABCDEFGHIJ) and functional dependencies {FDs=(AB->C,A->D,B->F,F->GH,D->IJ)} and decompositions

a) {D=(ABCDE,BFGH,DIJ)}

b) {D=(ABCD,DE,BF,FGH,DIJ)} Check whether the decomposition is lossless or not? 

Q2. Check whethe.r the given schedule S is conflict serializable or not? If yes, then Draw a precedence graph for it and give valid serial schedules possible using topological sort. S : R1(A) , R2(A) , R1(B) , R2(B) , R3(B) , W1(A) , W2(B)

Q1. B. Consider the Following Table Employee(emp_id, name,dept_id, email, mobile_number, join_date,salary, mgr_id) 1) Query to display the name and salary for all the employees whose salary is not in the range of Rs. 10,000 and 50,000. 2) Make sure that the EmailId of each employee is common and unique to that employee only. 3) Query to display the name and Department number of all the Employees in department number 8 and 12 in an alphabetical order by name. 4) Write a query to display the name of employees who have an ‘a’ and ‘e’ in their name. 5) Write a query to display the name, job, salary of all the employees whose job is clerk or teacher and whose salary is not equal to 15,000.

Consider the following schedule of transactions

R1(A) W1(A) R2(A) W2(B) W1(B) Commit1 Commit2

Which of the following properties are true for the above schedule and justify the reason for your answer

with explanation?

a) Conflict Serializable

b) View Serializable

c) Recoverable

Write short notes on Recoverability. 

What is scheduling and serializability of schedules?

What is concurrency control in transaction? 

Explain briefly about ACID properties.

Write short notes on the following with suitable examples.

a. 4NF b. 5NF