BARC 2020: DBMS Nuclear Quiz 1 (App update required to attempt this test)

In order to maintain the consistency during transaction database provides:

Consider a block size 512 bytes, search key field 9 bytes long, block pointer size 6 Bytes and record pointer 7 bytesq long. If a level 3 B+ Tree is constructed consiering root as level 0, find the maximum number of entries in the B+ tree as (34)^x*y entries and give the value for x+y.

Consider a sequence of 10 elements:

S = [-4, 6, -2, 3, -9,  8, -1, -7, 5]. The subsequence sum B (i, j) = . Determine the maximum of B (i. j), where 0 ≤ i < j.

Consider x as prime attribute and y as non - prime attribute of relation R(mnopqrst), from given functional dependencies: F = (q->rst, mn->pqrst, o->pq, p->m). Find the value of x*y.

Consider the following set of functional dependencies F on the schema (A, B, C)

F = {A->BC, B->C, A->B, AB->C} The canonical cover of this set is:

A relation R(A, B) has primary key is A and B is a foreign key refining the same relation R. Which of the following row sequence can be inserted into R?

Consider the SQL query:

Select ename from emp group by deptno

What is the output of the query?

Relation R(ABCDE) with ID set F = {A->BC, C->DE, D->E} and the decomposition {R1(ABCD) AND R2(DE)}

I. Loss less

II. Lossy

III. Dependency Preserving

IV. Not Dependency Preserving

Transactions T1, T2, T3 and T4 are entered into the system in the order T4, T3, T2 and T1. Transactions are requesting a data item held by another transactions in the following manner. Transaction T2 is requesting for a data item held by T3

Transaction T1 is requesting for a data item held by T2 Transaction T4 is requesting for a data item held by T3 Which of the following is true statement?

Database schema is given below: customer(customerId, Name, Phonenumber, address) account(accountNo, balance, branchName)

Find out the phonenumber and address of the customer named by Aditya in relatonal algebra from above database schema.