Database Management Systems – Previous Year Questions
218 questions from past UGC NET Paper 2 – Computer Science papers, each with the correct answer. Open any question for its explanation.
- Which of the following is consistent with this instance of R(X, Y, Z): (1, 1, a), (1, 1, a), (2, 1, b), (3, 2, b)?
- R1(Name, Class) = {(a1, 9), (b1, 5), (c1, 6), (d1, 11)} and R2(Name, Class) = {(b1, 5), (f1, 8)}. Which operation produces the output {(b1, 5)}?
- Match List I and List II
- Which relational algebra query computes the names of sailors who have reserved all boats?
- Which relational algebra query computes the names of sailors who have reserved a red and a green boat?
- Let R(ABCDEFGH) be a relation schema and F = {A → B, ABCD → E, EF → G, EF → H, ACDF → EG}. The minimal cover of this set of dependencies is
- A trigger is
- In reference to big data, consider the following databases: (A) Memcached (B) CouchDB (C) InfiniteGraph.
- Match List I with List II. List I: A. BCNF, B. 3NF, C. 2NF, D. 4NF. List II: I. Removes multivalued dependency, II. Not always dependency preserving, III. Removes transitive dependency, IV. Removes partial functional de…
- Statement I: Conservative 2PL is a deadlock-free protocol. Statement II: Thomas's write rule enforces conflict serializability. Statement III: Timestamp ordering ensures serializability based on the order of transaction…
- Statement I: Composite attributes cannot be divided into smaller subparts. Statement II: Complex attributes are formed by nesting composite and multivalued attributes in an arbitrary way. Statement III: A derived attrib…
- The order of a leaf node in a B+ tree is the maximum number of (value, data record pointer) pairs it can hold. Given a block size of 1K bytes, a 7-byte data record pointer, a 9-byte value field and a 6-byte block pointe…
- Which of the DBMS component ensures that concurrent execution of multiple operations on the database results into a consistent database state?
- Consider following two statements: Statement I: Relational database schema represents the logical design of the database. Statement II: Current snapshot of a relation only provides the degree of the relation. In the con…
- Given a fixed‐length record file that is ordered B on the key field. The file needs disk blocks to R store number of records. Find the average access time needed to access any record of the given file using binary searc…
- Given the following STUDENT‐COURSE scheme: STUDENT (Rollno, Name, courseno) COURSE (courseno, coursename, capacity), where Rollno is the primary key of relation STUDENT and courseno is the primary key of relation COURSE…
- Given STUDENT(Rollno, Name, Courseno) and COURSE(Courseno, Coursename, Capacity) with 5 and 3 records, R = STUDENT × COURSE is computed. Match List I with List II. List I: A. Degree of table R, B. Cardinality of table R…
- A B tree indexes a database file with search key 10 bytes, block 1024 bytes, record pointer 9 bytes and block pointer 8 bytes. If K is the order of the internal node and L the order of the leaf node, (K, L) =
- Given R(x, y, z, w) with F = {x → y, z → w}, where all attributes are atomic: A. R is in First Normal Form. B. R is in Second Normal Form. C. The primary key of R is xz.
- A company is consuming parts in the manufacturing of other products. Each of the part is either manufactured within the company or purchased from the external suppliers or both. For each part, partnumber, partname is ma…
- A transaction may be in one of the following states during its execution life cycle in concurrent execution environment. A. FAILED B. TERMINATED C. PARTIALLY COMMITTED D. COMMITTED E. ACTIVE Given a transaction in activ…
- Which of the following is used to create a database schema?
- The data node and name node in HADOOP are
- Consider a relational schema S = (U, V , W, X, Y , Z) on which the following functional dependencies hold: {U → V , V W → X, Y → W, X → U} Which are the candidate keys among following options?
- In the context of concurrency control, a given pair of operations in a schedule is called conflict schedule if (A) At least one of the operations is write operation. (B) Both the operations are performed on the same dat…
- Match List I with List II.
- On the basis of above given table structures, retrieve the distinct employee ID (EMPID) of all employees of university who are working on project No.20, 30 and 40.
- Given below are two statements to find the sum of salaries of all employees of the English department as well as the maximum, minimum and average salary in English department. STATEMENT I ： SELECT SUM (SALARY), MAX (SAL…
- Which of the following query/queries return the employee ID and name of employees whose salary is greater than the salary of all employees in department number 20 of university? Order results by employee ID (refer to ta…
- In reference to the above given table structures, which of the following query/queries will drop the 'SALARY' column from 'EMPLOYEE' table? (A) ALTER TABLE EMPLOYEE DROP SALARY CASCADE; (B) ALTER TABLE EMPLOYEE DROP SAL…