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MCQOPTIONS
This section includes 1917 Mcqs, each offering curated multiple-choice questions to sharpen your UGC-NET knowledge and support exam preparation. Choose a topic below to get started.
| 1101. |
In RDBMS, the constraint that no key attribute (column) may be NULL is referred to as: |
| A. | Referential integrity |
| B. | Multi-valued dependency |
| C. | Entity Integrity |
| D. | Functional dependency |
| Answer» D. Functional dependency | |
| 1102. |
In the indexed scheme of blocks to a file, the maximum possible size of the file depends on : |
| A. | The number of blocks used for index and the size of index |
| B. | Size of Blocks and size of Address |
| C. | Size of index |
| D. | Size of Block |
| Answer» B. Size of Blocks and size of Address | |
| 1103. |
Match the following with respect to the jump statements List-I List-IIa. Timeout ordering protocol i. Wait for graphb. Deadlock prevention ii. Roll backc. Deadlock detection iii. Wait-die schemed. Deadlock recovery iv. Thomas Write RuleCodes:a b c d |
| A. | iv iii i ii |
| B. | iii ii iv i |
| C. | ii i iv iii |
| D. | iii i iv ii |
| Answer» B. iii ii iv i | |
| 1104. |
In a Hierachical database, a hashing function is used to locate the ................. |
| A. | Collision |
| B. | Root |
| C. | Foreign Key |
| D. | Records |
| Answer» C. Foreign Key | |
| 1105. |
Consider the following two commands C1 and C2 on the relation R from an SQL database:C1: drop table R;C2: delete from R;Which of the following statements is TRUE?I. Both C1 and C2 delete the schema for R.II. C2 retains relation R, but deletes all tuples in R.III. C1 deletes not only all tuples of R, but also the schema for R. |
| A. | I only |
| B. | I and II only |
| C. | II and III only |
| D. | I, II and III |
| Answer» D. I, II and III | |
| 1106. |
An embedded pointer provides: |
| A. | Physical record key |
| B. | An inserted Index |
| C. | A secondary access path |
| D. | All the above |
| Answer» D. All the above | |
| 1107. |
In a relational database model, NULL values can be used for all but which one of the following? |
| A. | To allow duplicate tuples in the table by filling the primary key column(s) with NULL |
| B. | To avoid confusion with actual legitimate data values like 0 (zero) or integer columns and " (the empty string) for string columns |
| C. | To leave columns in a tuple marked as "unknown" when the actual value is unknown |
| D. | To fill a column in a tuple when that column does not really "exist" for that particular tuple |
| Answer» B. To avoid confusion with actual legitimate data values like 0 (zero) or integer columns and " (the empty string) for string columns | |
| 1108. |
A chained hash table has an array size of 100. What is the maximum number of entries that can be placed in the table? |
| A. | 100 |
| B. | 200 |
| C. | 10000 |
| D. | There is no upper limit |
| Answer» E. | |
| 1109. |
Match the following database terms to their functions:List-I List-II(a) Normalization (i) Enforces match of primary key to foreign key(b) Data Dictionary (ii) Reduces data redundancy in a database(c) Referential Integrity (iii) Define view(s) of the database for particular user(s).(d) External Schema (iv) Contains metadata describing database structure.Codes: (a) (b) (c) (d) |
| A. | (iv) (iii) (i) (ii) |
| B. | (ii) (iv) (i) (iii) |
| C. | (ii) (iv) (iii) (i) |
| D. | (iv) (iii) (ii) (i) |
| Answer» C. (ii) (iv) (iii) (i) | |
| 1110. |
Division operation is ideally suited to handle queries of the type : |
| A. | customers who have no account in any of the branches in Delhi |
| B. | customers who have an account at all branches in Delhi |
| C. | customers who have an account in at least one branch in Delhi |
| D. | customers who have only joint account in any one branch in Delhi |
| Answer» C. customers who have an account in at least one branch in Delhi | |
| 1111. |
Consider the query : SELECT student_name FROM student_data WHERE rollno (SELECT rollno FROM student_marks WHERE SEM1_MARK=SEM2_MARK);Which of the following is true? |
| A. | It gives the name of the student whose marks in semester 1 and semester 2 are same. |
| B. | It gives all the names and roll nos of those students whose marks in semester 1 and semester 2 are same. |
| C. | It gives the names of all the students whose marks in semester 1 and semester 2 are same. |
| D. | It gives roll numbers of all students whose marks in semester 1 and semester 2 are same. |
| Answer» D. It gives roll numbers of all students whose marks in semester 1 and semester 2 are same. | |
| 1112. |
If D1, D2,…. Dn are domains in a relational model, then the relation is a table, which is a subset of |
| A. | D1+D2+…. +Dn |
| B. | D1x D2x… xDn |
| C. | D1U D2U….UDn |
| D. | D1- D2-….-Dn |
| Answer» C. D1U D2U….UDn | |
| 1113. |
Which of the following is correct?I. Two phase locking is an optimistic protocol.II. Two phase locking is pessimistic protocolIII. Time stamping is an optimistic protocol.IV. Time stamping is pessimistic protocol. |
| A. | I and III |
| B. | II and IV |
| C. | I and IV |
| D. | II and III |
| Answer» D. II and III | |
| 1114. |
A locked file can be: |
| A. | accessed by only one user |
| B. | modified by users with the correct password |
| C. | is used to hide sensitive information |
| D. | both b and c |
| Answer» B. modified by users with the correct password | |
| 1115. |
________________rules used to limit the volume of log information that has to be handled and processed in the event of system failure involving the loss of volatile information. |
| A. | Write-ahead log |
| B. | Check-pointing |
| C. | Log buffer |
| D. | Thomas |
| Answer» C. Log buffer | |
| 1116. |
An attribute A of datatype varchar(20) has the value ‘xyz’, and the attribute B of datatype char(20) has the value “lmnop”, then the attribute A has ............... spaces and attribute B has ............... spaces. |
| A. | 3,5 |
| B. | 20,20 |
| C. | 3,20 |
| D. | 20,5 |
| Answer» D. 20,5 | |
| 1117. |
Which of the following concurrency protocol ensures both conflict serializability and freedom from deadlock ?(a) 2-phase Locking(b) Time stamp - ordering |
| A. | Both (a) and (b) |
| B. | (a) only |
| C. | (b) only |
| D. | Neither (a) nor (b) |
| Answer» D. Neither (a) nor (b) | |
| 1118. |
Which of the following is true?I. Implementation of self-join is possible in SQL with table alias.II. Outer-join operation is basic operation in relational algebra.III. Natural join and outer join operations are equivalent. |
| A. | I and II are correct |
| B. | II and III are correct |
| C. | Only III is correct |
| D. | Only I is correct |
| Answer» E. | |
| 1119. |
Let R = ABCDE is a relational scheme with functional dependency set F = {A -> B, B ->C,AC -> D}. The attribute closures of A and E are |
| A. | ABCD, Ø |
| B. | ABCD, E |
| C. | ɸ , Ø |
| D. | ABC, E |
| Answer» C. ɸ , Ø | |
| 1120. |
Data which improves the performance and accessibility of the database are called: |
| A. | Indexes |
| B. | User Data |
| C. | Application Metadata |
| D. | Data Dictionary |
| Answer» B. User Data | |
| 1121. |
Multi-valued dependency among attribute is checked at which level ? |
| A. | 2 NF |
| B. | 3 NF |
| C. | 4 NF |
| D. | 5 NF |
| Answer» D. 5 NF | |
| 1122. |
A function that has no partial functional dependencies is in ……………. form. |
| A. | 3 NF |
| B. | 2 NF |
| C. | 4 NF |
| D. | BCNF |
| Answer» C. 4 NF | |
| 1123. |
Which of the following statements regarding the features of the object-oriented approach to databases are true ?(a) The ability to develop more realistic models of the real world.(b) The ability to represent the world in a non-geometric way.(c) The ability to develop databases using natural language approaches.(d) The need to split objects into their component parts.(e) The ability to develop database models based on location rather than state and behaviour. |
| A. | (a), (b) and (c) |
| B. | (b), (c) and (d) |
| C. | (a), (d) and (e) |
| D. | (c), (d) and (e) |
| Answer» B. (b), (c) and (d) | |
| 1124. |
Consider a schema R(A, B, C, D) and following functional dependencies.A → BB → CC → DD → BThen decomposition of R into R1(A, B), R2(B, C) and R3(B, D) is .................. |
| A. | Dependency preserving and lossless join. |
| B. | Lossless join but not dependency preserving. |
| C. | Dependency preserving but not lossless join. |
| D. | Not dependency preserving and not lossless join. |
| Answer» B. Lossless join but not dependency preserving. | |
| 1125. |
In SQL, .................. is an Aggregate function. |
| A. | SELECT |
| B. | CREATE |
| C. | AVG |
| D. | MODIFY |
| Answer» D. MODIFY | |
| 1126. |
The best normal form of relation scheme R(A. B, C, D) along with the set of functional dependencies F = {AB → C, AB → D, C → A, D → B} is |
| A. | Boyce-Codd Normal form |
| B. | Third Normal form |
| C. | Second Normal form |
| D. | First Normal form |
| Answer» D. First Normal form | |
| 1127. |
Data Integrity control uses _______________ |
| A. | Upper and lower limits on numeric data |
| B. | Passwords to prohibit unauthorized access to files |
| C. | Data dictionary to keep the data |
| D. | Data dictionary to find last access of data |
| Answer» E. | |
| 1128. |
Armstrong (1974) proposed systematic approach to derive functional dependencies. Match the following w.r.t. functional dependencies:a.Decomposition Rule (i) If X →Y and Z →W then {X, Z} → {Y, W}b. Union Rule (ii) If X →Y an {Y,W} → Z then {X, W} → Zc. Composition Rule (iii) If X →Y and X →Z then X → {Y, Z} d. Pseudo transitivity Rule (iv) If X →{Y,Z} and {Y,W} → Z then X → Y and X →Z |
| A. | (a)-(iii),(b)-(ii),(c)-(iv),(d)-(i) |
| B. | (a)-(i),(b)-(iii),(c)-(iv),(d)-(ii) |
| C. | (a)-(ii),(b)-(i),(c)-(iii),(d)-(iv) |
| D. | (a)-(iv),(b)-(iii),(c)-(i),(d)-(ii) |
| Answer» E. | |
| 1129. |
Find the false statement : |
| A. | The relationship construct known as the weak relationship type was defined by Dey, Storey & Barron (1999) |
| B. | A weak relationship occurs when two relationship types are linked by either Event- Precedent sequence or Condition-Precedent sequence |
| C. | Conceptual model is not accurate representation of "Universe of interest" |
| D. | Ternary, Quaternary and Quintary relationships are shown through a series of application scenario's and vignette's |
| Answer» C. Conceptual model is not accurate representation of "Universe of interest" | |
| 1130. |
Match the following:List - I List - IIa. Secondary i. Functional DependencyIndexb. Nonprocedural ii. B-TreeQueryLanguagec. Closure of iii. Relational Algebraicset of OperationAttributesd. Natural iv. Domain CalculusJOIN |
| A. | (a)-(i),(b)-(ii),(c)-(iv),(d)-(iii) |
| B. | (a)-(ii),(b)-(i),(c)-(iv),(d)-(iii) |
| C. | (a)-(i),(b)-(ii),(c)-(iv),(d)-(iii) |
| D. | (a)-(ii),(b)-(vi),(c)-(iii),(d)-(i) |
| Answer» E. | |
| 1131. |
The E-R model is expressed in term ofI. EntitiesII. The relationship among entities.III. The attributes of the entities.IV. Functional relationship. |
| A. | I, II |
| B. | I, II, IV |
| C. | II, II, IV |
| D. | I, II, III |
| Answer» E. | |
| 1132. |
For a database relation R(a, b, c, d) where the domains of a, b, c, d include only the atomic values. The functional dependency a → c, b → d holds in the following relation |
| A. | In 1NF not in 2NF |
| B. | In 2NF not in 3NF |
| C. | In 3NF |
| D. | In 1NF |
| Answer» B. In 2NF not in 3NF | |
| 1133. |
Aggregation is: |
| A. | an abstraction through which relationships are treated as lower level entities |
| B. | an abstraction through which relationships are treated as higher level entities |
| C. | an abstraction through which relationships are not treated at all as entities |
| D. | none of the above |
| Answer» C. an abstraction through which relationships are not treated at all as entities | |
| 1134. |
Relations produced from E - R Model will always be in .............. |
| A. | 1 NF |
| B. | 2 NF |
| C. | 3 NF |
| D. | 4 NF |
| Answer» D. 4 NF | |
| 1135. |
Consider the following sequence of two transactions on a bank account (A) with initial balance 20,000 that transfers 5,000 to another account (B) and then apply 10% interest.(i) T1 start(ii) T1 A old = 20,000 new 15,000(iii) T1 B old = 12,000 new = 17,000(iv) T1 commit(v) T2 start(vi) T2 A old = 15,000 new = 16,500(vii) T2 commitSuppose the database system crashes just before log record (vii) is written. When the system is restarted, which one statement is true of the recovery process? |
| A. | We must redo log record (vi) to set A to 16,500. |
| B. | We must redo log record (vi) to set A to 16,500 and then redo log records (ii) and (iii). |
| C. | We need not redo log records (ii) and (iii) because transaction T1 is committed. |
| D. | We can apply redo and undo operations in arbitrary order because they are idempotent. |
| Answer» C. We need not redo log records (ii) and (iii) because transaction T1 is committed. | |
| 1136. |
DBMS provides the facility of accessing data from a database through |
| A. | DDL |
| B. | DML |
| C. | DBA |
| D. | Schema |
| Answer» C. DBA | |
| 1137. |
The Relation Vendor Order (V_no, V_ord_no, V_name, Qty_sup, unit_price) is in 2NF because: |
| A. | Non_key attribute V_name is dependent on V_no which is part of composite key |
| B. | Non_key attribute V_name is dependent on Qty_sup |
| C. | Key attribute Qty_sup is dependent on primary_key unit price |
| D. | Key attribute V_ord_no is dependent on primary_key unit price |
| Answer» B. Non_key attribute V_name is dependent on Qty_sup | |
| 1138. |
An ER Model includes1. An ER diagram portraying entity types.II. Attributes for each entity typeIII. Relationships among . entity types.IV. Semantic integrity constraints that reflects the business rules about data not captured in the ERdiagram. |
| A. | I, II, III & IV |
| B. | I & IV |
| C. | I, II & IV |
| D. | I & III |
| Answer» B. I & IV | |
| 1139. |
A relation R on a set X is said to be a partial ordering if R is |
| A. | Reflexive, Symmetric, Transitive |
| B. | Reflexive, Symmetric, Non-Transitive |
| C. | Reflexive, Anti-Symmetric, Transitive |
| D. | Reflexive, Anti-Symmetric, Non-Transitive |
| Answer» D. Reflexive, Anti-Symmetric, Non-Transitive | |
| 1140. |
Consider a schema R(A, B, C, D) and functional dependencies A->B and C->D. Then the decomposition R1(A, B) and R2(C, D) is |
| A. | Dependency preserving but not lossless join |
| B. | Dependency preserving and lossless join |
| C. | Lossless Join but not dependency preserving |
| D. | Lossless Join |
| Answer» B. Dependency preserving and lossless join | |
| 1141. |
The student marks should not be greater than 100. This is |
| A. | Integrity constraint |
| B. | Referential constraint |
| C. | Over-defined constraint |
| D. | Feasible constraint |
| Answer» B. Referential constraint | |
| 1142. |
Two phase protocol in a database management system is: |
| A. | a concurrency mechanism that is not deadlock free |
| B. | a recovery protocol used for restoring a database after a crash |
| C. | Any update to the system log done in 2-phases |
| D. | not effective in Database |
| Answer» B. a recovery protocol used for restoring a database after a crash | |
| 1143. |
Consider the query : SELECT student_name FROM students WHERE class_name=(SELECT class_name FROM students WHERE math_marks=100); what will be the output ? |
| A. | the list of names of students with 100 marks in mathematics |
| B. | the names of all students of all classes in which at least one student has 100 marks in mathematics |
| C. | the names of all students in all classes having 100 marks in mathematics |
| D. | the names and class of all students whose marks in mathematics is 100 |
| Answer» C. the names of all students in all classes having 100 marks in mathematics | |
| 1144. |
If a relation is in 2NF and 3NF forms then: |
| A. | no non-prime attribute is functionally dependent on other non-prime attributes |
| B. | no non-prime attribute is functionally dependent on prime attributes |
| C. | all attributes are functionally independent |
| D. | prime attribute is functionally independent of all non-prime attributes |
| Answer» B. no non-prime attribute is functionally dependent on prime attributes | |
| 1145. |
In a heap, every element is …………… of all the elements in the subtree. |
| A. | maximum |
| B. | minimum |
| C. | sum |
| D. | product |
| Answer» B. minimum | |
| 1146. |
Consider the following ORACLE relations:R(A,B,C) = {, , , , , }S(B,C,D) = {, , , , }Consider the following two SQL queries SQ1 and SQ2:SQ1: SELECT R.B, AVG(S.B)FROM R, SWHERE R.A = S.C AND S.D < 7GROUP BY R.B;SQ2: SELECT DISTINCT S.B, MIN (S.C)FROM SGROUP BY S.BHAVING COUNT (DISTINCT S.D) > 1;If M is the number of tuples returned by SQ1 and N is the number of tuples returned by SQ2 then |
| A. | M=4, N=2 |
| B. | M=5, N=3 |
| C. | M=2, N=2 |
| D. | M=3, N=3 |
| Answer» B. M=5, N=3 | |
| 1147. |
.................. constraints ensure that a value that appears in one relation for a given set of attributes also appears for a certain set of attributes in another relation. |
| A. | Logical Integrity |
| B. | Referential Integrity |
| C. | Domain Integrity |
| D. | Data Integrity |
| Answer» C. Domain Integrity | |
| 1148. |
What deletes the entire file except the file structure ? |
| A. | ERASE |
| B. | DELETE |
| C. | ZAP |
| D. | PACK |
| Answer» D. PACK | |
| 1149. |
Consider a “CUSTOMERS” database table having a column “CITY” filled with all the names of Indian cities (in capital letters). The SQL statement that finds all cities that have “GAR” somewhere in its name, is: |
| A. | Select *from customers where city=’%GAR%’; |
| B. | Select *from customers where city=’$GAR$’; |
| C. | Select *from customers where city like ‘%GAR%’; |
| D. | Select *from customers where city as ’%GAR’; |
| Answer» D. Select *from customers where city as ’%GAR’; | |
| 1150. |
Identify the minimal key for relational scheme R(A, B, C, D, E) with functional dependencies F = {A → B, B → C, AC → D} |
| A. | A |
| B. | AE |
| C. | BE |
| D. | CE |
| Answer» C. BE | |