561. Normalization is NOT for which purpose?

Databases • Normalization • UGC NET Paper 2 Computer Science AUG 2016

562. For R(A,B,C) with FDs A→B, C→AB, which true? I. decompose into (C,A)&(A,B) is lossless. II. decompose into (A,B)&(B,C) is lossy.

Databases • Normalization • UGC NET Paper 2 Computer Science AUG 2016

563. Which are True for OODBMS vs RDBMS? I. avoids impedance mismatch. II. avoids phantom problem. III. higher concurrency. IV. faster object access.

Databases • Object s • UGC NET Paper 2 Computer Science AUG 2016

564. Regarding relational model statements (a),(b),(c), which are true?

Databases • Relational Theory • UGC NET Paper 2 Computer Science AUG 2016

565. DBMS lets users access data via which language?

Databases • SQL • UGC NET Paper 2 Computer Science AUG 2016

566. Which SQL query on R(A,B) is illegal?

Databases • SQL Grouping • UGC NET Paper 2 Computer Science AUG 2016

567. One EXCEPT and EXCEPT ALL cardinalities?

Databases • SQL set operators • UGC NET Paper 2 Computer Science AUG 2016

568. In RDBMS, the constraint that no key attribute may be NULL is called?

Databases • Constraints – Entity Integrity • UGC NET Paper 2 Computer Science AUG 2016

569. (A) Data scrubbing upgrades data quality before moving to DW; (B) Scrubbing rejects data from DW to create indexes. Which?

Databases • Data Warehousing • UGC NET Paper 2 Computer Science AUG 2016

570. (A) BI/DW used for forecasting and data mining; (B) BI/DW used for analysis of large sales data. Which?

Databases • Data Warehousing & BI • UGC NET Paper 2 Computer Science AUG 2016

571. Which of the following is a semi-join technique?

Databases • Distributed Query Processing: Semi-joins • UGC NET Paper 2 Computer Science AUG 2016

572. In distributed s, location transparency allows users to treat the data as if at one location. A SQL query with location transparency needs to specify:

Databases • Distributed s: Location Transparency • UGC NET Paper 2 Computer Science AUG 2016

573. Given candidate keys {B}, {B,C}, {A,D}, {C,D}, which could not be a key if all attribute symbols are distinct?

Databases • Keys and Superkeys • UGC NET Paper 2 Computer Science AUG 2016

574. Which statement is TRUE? D1: decomposition of R(A,B,C) into R1(A,B) and R2(A,C) is always lossless; D2: decomposition of R(A,B,C,D,E) with AD→B, C→DE, B→AE, AE→C into R1(A,B,D) and R2(A,C,D,E) is lossless.

Databases • Normalization & Lossless Decomposition • UGC NET Paper 2 Computer Science AUG 2016

575. In a relational model, NULL values cannot be used to:?

Databases • Null Semantics • UGC NET Paper 2 Computer Science AUG 2016

576. Which is FALSE about OODB? Objects contain data and methods; They store instructions with data; They handle analytical data better than relational; They store more types and access faster.

Databases • Object-Oriented s • UGC NET Paper 2 Computer Science AUG 2016

577. Consider R(A,B) and S(B,C) and these relational‐algebra queries: I. ΠA,B(R⋈S) II. R⋈ΠB(S) III. R∩(ΠA(R)×ΠB(S)) IV. ΠA,R.B(R×S). Which queries are equivalent?

Databases • Relational Algebra Equivalences • UGC NET Paper 2 Computer Science AUG 2016

578. Which is FALSE in RDBMS: I. Views help access control; II. E-R diagrams model concepts; III. Update anomaly stores unrelated info; IV. SQL is procedural?

Databases • Relational Concepts • UGC NET Paper 2 Computer Science AUG 2016

579. Consider C1: `DROP TABLE R;` C2: `DELETE FROM R;` Which is TRUE: I. Both delete schema; II. C2 retains schema; III. C1 deletes schema?

Databases • SQL Data Definition vs Manipulation • UGC NET Paper 2 Computer Science AUG 2016

580. Given R(A,B,C) and S(B,C,D): R={(1,1,10),(2,2,20),(3,3,30),(4,4,40)}, S={(1,1,100),(2,2,200),(5,5,500)}. SQ1: NATURAL JOIN, SQ2: INNER JOIN USING(B,C). Tuples M,N?

Databases • SQL Joins • UGC NET Paper 2 Computer Science AUG 2016