Top 1000+ Solved DataBase Management System (DBMS) MCQ Questions Answer
Q. Weak entity set is represented as
a. underline
b. double line
c. double diamond
d. double rectangle
Q. We indicate roles in E-R diagrams by labeling the lines that connect to
a. diamond , diamond
b. rectangle, diamond
c. rectangle, rectangle
d. diamond, rectangle
Q. For a weak entity set to be meaningful, it must be associated with another entity set, called the
a. identifying set
b. owner set
c. neighbour set
d. strong entity set
Q. If you were collecting and storing information about your music collection, an album would be considered a(n)
a. relation
b. entity
c. instance
d. attribute
Q. Which one of the following can be treated as a primary key in teaches relation?
a. id
b. semester
c. sec_id
d. year
Q. The primary key in the section relation is
a. course_id
b. sec_id
c. both course_id and sec_id
d. all the attributes
Q. The relation with primary key can be created using
a. create table instructor (id, name)
b. create table instructor (id, name, primary key(name))
c. create table instructor (id, name, primary key (id))
d. create table instructor ( id unique, name )
Q. How can the values in the relation teaches be deleted?
a. drop table teaches;
b. delete from teaches;
c. purge table teaches;
d. delete from teaches where id =’null’;
Q. The total participation by entities is represented in E-R diagram as
a. dashed line
b. double line
c. double rectangle
d. circle
Q. Given the basic ER and relational models, which of the following is INCORRECT?
a. an attribute of an entity can have more than one value
b. an attribute of an entity can be composite
c. in a row of a relational table, an attribute can have more than one value
d. in a row of a relational table, an attribute can have exactly one value or a null value
Q. Which of the following indicates the maximum number of entities that can be involved in a relationship?
a. minimum cardinality
b. maximum cardinality
c. erd
d. greater entity count
Q. In E-R diagram generalization is represented by
a. ellipse
b. dashed ellipse
c. rectangle
d. triangle