Relational Model in DBMS
Dr.E.F. Codd worked to improve the working of DBMSs to handle large volumes of data. He applied the rules of mathematics to solve the problems of earlier database models. Some important problems were as follows:
- Data Integrity
- Data Redundancy
Database mcqs with answers set 8 includes the mcqs of relational database model, basics of relational database model, primary key, attributes, cardinality and candidate key. These database mcqs are very helpful for those who are preparing any computer related PPSC, SPSC, FPSC, KPPSC OR CSS based private or government jobs. Its also very helpful for international students who want to be appear in Oracle certification exams.
DBMS MCQs - Database MCQs With Answers Set 8
1. The columns of a table correspond to _____?A). Table
B). Record
C). Field
D). Cell
View Answer
Correct: C
2. The foreign key is found in _____ ?
A). Parent table
B). Dependent table
C). Pivot table
D). Index table
View Answer
Correct: B
3. A table must have _____ ?
A). Primary key
B). Secondary key
C). Composite key
D). Sort key
View Answer
Correct: A
4. A two-dimensional table of data is called a _____?
A). Group
B). Set
C). Declaration
D). Relation
View Answer
Correct: D
5. A table is perceived as two-dimensional structure composed of _____?
A). X and y co-ordinates
B). Matrix elements
C). Rows and columns
D). Intersection of data
View Answer
Correct: C
6. A relation is analogous to a _____?
A). File
B). Field
C). Record
D). Row
View Answer
Correct: A
7. A relation is also known as _____?
A). Table
B). Tuple
C). Relationship
D). Attribute
View Answer
Correct: A
8. An attribute is also known as a _____?
A). Table
B). Relation
C). Row
D). Field
View Answer
Correct: D
9. A row of a relation is called a (n) _____?
A). Attribute
B). Entity
C). Tuple
D). Both a and c
View Answer
Correct: C
10. A person, place, thing, event, or condition about which data is kept in the database is called _____?
A). Attribute
B). Field
C). Record
D). Entity
View Answer
Correct: D
11. A category of data or information that describes an entity is called a(n) _____?
A). Attribute
B). Data item
C). Record
D). Tuple
View Answer
Correct: A
12. Which of the following is NOT a general characteristic of relations _____?
A). Each row is unique
B). The order of columns is significant
C). The order of rows is insignificant
D). Columns are all elemental or atomic
View Answer
Correct: B
13. An index can be used to _____?
A). Improve the performance of the database
B). Document the structure of the database itself
C). Reduce data dependency for application programs
D). All
View Answer
Correct: A
14. Which of the following are properties of relations _____?
A). Each attribute has a unique name
B). No two rows in a relation are identical
C). There are no multivalued attributes in a relation
D). All of the above
View Answer
Correct: D
15. A key is _____?
A). A field that identifies only one record
B). The most important field in a record
C). The first field of table
D). None
View Answer
Correct: A
16. Which of the following describes the primary key _____?
A). It must be unique
B). It helps in indexing of a large database
C). It makes sorting quicker
D). All of the above
View Answer
Correct: D
17. Which of the following is NOT a good primary key _____?
A). Social security number
B). Order number
C). Zip code
D). Student ID number
View Answer
Correct: C
18. How many primary keys can a table have _____?
A). One
B). At least one, but not more than two
C). Between 1 and 5
D). No limit
View Answer
Correct: A
19. Which of the following should be a primary key _____?
A). A person's last name
B). An employee's salary
C). A customer's ID number
D). A salesperson's region
View Answer
Correct: C
20. Which field listed below is the most appropriate primary key _____?
A). A person's name
B). A person's street address
C). A person's birth date
D). A person's Social Security Number
View Answer
Correct: D
21. One field or combination of fields for which more than one record may have the same combination of values is called _____?
A). Secondary key
B). Index
C). Composite key
D). Linked key
View Answer
Correct: A
22. A candidate key is _____?
A). Primary key
B). The primary key selected to be the key of a relation
C). An attribute or group of attributes that can be the primary key
D). All
View Answer
Correct: C
23. An attribute in a relation of a database that serves as the primary key of another relation in the same database is called a _____?
A). Global key
B). Link key
C). Foreign key
D). None
View Answer
Correct: C
24. A primary key that consists of more than one attribute is called a _____?
A). Foreign key
B). Composite key
C). Multivalued key
D). Global key
View Answer
Correct: B
25. In 3NF, which form of dependency is removed _____?
A). Functional
B). Non-functional
C). Associative
D). Transitive
View Answer
Correct: D
26. In relational database, table is also called _____?
A). Tuple
B). Relation
C). File
D). Schema
View Answer
Correct: B
