Database Management System MCQs with Answers
Practice important Database Management System MCQs with answers and explanations.
Chapter: 36
Q601:
When using re-hashing, what is done when a collision occurs?
A. A new hash function is applied to find an empty slot
B. The original hash function is re-applied until an empty slot is found
C. The record is moved to a different bucket
D. The search key is discarded
Correct Answer:
A
Chapter: 36
Q602:
Which collision handling technique involves using an overflow area for new elements?
A. Chaining
B. Overflow areas
C. Re-hashing
D. Linear probing
Correct Answer:
B
Chapter: 36
Q603:
In open addressing, what happens when a collision occurs?
A. The entry is inserted at an alternative location in the array
B. The record is stored in a linked list
C. The search key is ignored
D. A new hash table is created
Correct Answer:
A
Chapter: 36
Q604:
Fill in the blank: In hashing, the address of a data item is computed using a _______ on the search key value.
A. hash function
B. linear function
C. lookup table
D. direct mapping
Correct Answer:
A
Chapter: 36
Q605:
Fill in the blank: In hashing, if multiple keys map to the same bucket address, a _______ is needed to handle the collision.
A. chaining function
B. secondary index
C. hash function
D. handling technique
Correct Answer:
A
Chapter: 37
Q606:
What is an index in a database similar to in a book?
A. A table of contents
B. A list of page numbers
C. A list of words and their page numbers
D. A list of authors
Correct Answer:
A
Chapter: 37
Q607:
What is the main purpose of an index in a database?
A. To sort records sequentially
B. To find data quickly without scanning the entire table
C. To create new records
D. To delete old records
Correct Answer:
B
Chapter: 37
Q608:
Which type of index allows efficient search on any leading subset of the search key?
A. Hash index
B. Primary index
C. B-tree index
D. Secondary index
Correct Answer:
C
Chapter: 37
Q609:
What is a B-tree used for in databases?
A. Storing data in a sequential order
B. Sorting data by primary key
C. Implementing indexes with efficient search capabilities
D. Managing non-key attributes
Correct Answer:
C
Chapter: 37
Q610:
What happens if two indexes have the same key value in a database?
A. A collision occurs, and both indexes will point to the same data
B. A new index is created for the second key value
C. The first index is overwritten by the second index
D. The search key is discarded
Correct Answer:
A
Chapter: 37
Q611:
Which type of index involves ordering records based on non-key attributes?
A. Primary index
B. Composite index
C. Secondary index
D. Hash index
Correct Answer:
C
Chapter: 37
Q612:
Fill in the blank: An index in a database helps to find data quickly by _______ the entire table.
A. scanning
B. reading
C. skipping
D. sorting
Correct Answer:
C
Chapter: 37
Q613:
Fill in the blank: A __________ index is used to store records in order of a primary key attribute.
A. primary
B. secondary
C. unique
D. composite
Correct Answer:
A
Chapter: 37
Q614:
What is a composite index?
A. A single index on one column
B. A unique index on a column
C. A multiple-column index
D. A hash index
Correct Answer:
C
Chapter: 37
Q615:
Fill in the blank: The SQL command to create an index on a table column is _______.
A. CREATE INDEX
B. CREATE TABLE
C. CREATE VIEW
D. CREATE FUNCTION
Correct Answer:
A
Chapter: 37
Q616:
Which index classification allows searching on multiple columns?
A. Single Key Index
B. Composite Index
C. Tree-based Index
D. Secondary Index
Correct Answer:
B
Chapter: 37
Q617:
What are the two major types of indexes in databases?
A. Primary and Secondary Indexes
B. Clustered and Un-clustered Indexes
C. Composite and Single Key Indexes
D. Tree-based and Hash Indexes
Correct Answer:
B
Chapter: 37
Q618:
Fill in the blank: __________ indexes support equality selections.
A. Tree
B. Hash
C. Composite
D. Secondary
Correct Answer:
B
Chapter: 37
Q619:
Which indexing technique uses a two-column file to store addresses of tuples?
A. Primary Index
B. Secondary Index
C. B-tree Index
D. Hash Index
Correct Answer:
B
Chapter: 37
Q620:
Fill in the blank: The SQL command `CREATE UNIQUE INDEX pr_prName ON program(prName)` creates an index on a _______.
A. single column
B. multiple columns
C. primary key
D. foreign key
Correct Answer:
A