DBMS MCQ Questions

Q.1           In the relational modes, cardinality is termed as:

               (A)   Number of tuples.                    (B)   Number of attributes.

               (C)   Number of tables.                    (D)   Number of constraints.

               Ans: A

Q.2           Relational calculus is a

               (A)   Procedural language.                 (B)   Non- Procedural language.

               (C)   Data definition language.             (D)  High level language.

               Ans: B

Q.3           The view of total database content is

               (A)  Conceptual view.                      (B)  Internal view.

               (C)  External view.                        (D)  Physical View.

               Ans: A

Q.4           Cartesian product in relational algebra is

               (A)  a Unary operator.                     (B)  a Binary operator.

              (C)  a Ternary operator.                    (D)  not defined.

               Ans: B    Cartesian product in relational algebra is a binary operator.

                     (It requires two operands. e.g., P X Q)

Q.5           DML is provided for

(A)    Description of logical structure of database.

               (B)    Addition of new structures in the database system.

               (C)    Manipulation & processing of database.

               (D)    Definition of physical structure of database system.

               Ans: C    DML is provided for manipulation & processing of database.                       (Data   stored   in   the   database   is   processed   or   manipulated   using   data   manipulation

                     language commands as its name)

Q.6           ‘AS’ clause is used in SQL for

              (A)   Selection operation.                (B)  Rename operation.

              (C)   Join operation.                     (D)  Projection operation.

               Ans: B   ‘AS’ clause is used in SQL for rename operation.

                    (e.g., SELECT ENO AS EMPLOYEE_NO FROM EMP)

Q.7           ODBC stands for

               (A)  Object Database Connectivity.

               (B)  Oral Database Connectivity.

               (C)  Oracle Database Connectivity.

               (D)  Open Database Connectivity.

               Ans: D

Q.8           Architecture of the database can be viewed as

              (A)   two levels.                 (B)     four levels.

              (C)   three levels.               (D)     one level.

               Ans: C

Q.9           In a relational model, relations are termed as

              (A)  Tuples.                              (B)  Attributes

              (C)  Tables.                              (D)  Rows.

               Ans:

Q.10          The database schema is written in

              (A)   HLL                                 (B)  DML

               (C)  DDL                                 (D)  DCL

               Ans: C

Q.11          In the architecture of a database system external level is the

              (A)  physical level.                      (B)    logical level.

              (C)  conceptual   level                   (D)    view level.

               Ans: D

Q.12          An entity set that does not have sufficient attributes to form a primary key is a

              (A)  strong entity set.                   (B)  weak entity set.

              (C)  simple entity set.                   (D)  primary entity set.

               Ans: B

Q.13         In an E-R diagram attributes are represented by

               (A)     rectangle.                             (B)  square.

               (C)     ellipse.                               (D)  triangle.

                Ans: C

Q.14          In case of entity integrity, the primary key may be

               (A)     not Null                               (B)  Null

               (C)     both Null & not Null.                  (D)  any value.

                Ans: A

Q.15          In tuple relational calculus  P1 → P2  is equivalent to

               (A) ¬P  ∨ P                           (B)      P  ∨ P

                        1    2                                 1     2

               (C)    P  ∧ P                         (D)      P  ∧ ¬P

                        1    2                                 1       2

                Ans: A    In tuple relational calculus P       P  is equivalent to ¬P        ∨ P  .

                                                            1      2                       1     2

                (The logical implication expression A  B, meaning if A then B,is equivalent to ¬A ∨ B)