Q44.Marks: +2.0UGC NET Paper 2: Computer Science 7th Dec 2023 Shift 2
Which of the following is/are NOT CORRECT statement?
(A) The first record in each block of the data file is known as actor record.
(B) Dense index has index entries for every search key value in the data file.
(C) Searching is harder in the B+ tree than B- tree as the all external nodes linked to each other.
(D) In extendible hashing the size of directory is just an array of 2d-1, where d is global depth.
Choose the correct answer from the options given below:
1.(A), (B) and (C) Only
2.(A), (C) and (D) Only ✓ Correct
3.(A), (B) and (D) Only
4.(A), (B), (C) and (D) Only
Solution
The correct answer is (A), (C) and (D) Only
EXPLANATION:
(A) The first record in each block of the data file is known as actor record.
The first record in each block of the data file is not known as an actor record, this seems to be an incorrect usage of terminology in the context of databases.
(C) Searching is harder in the B+ tree than B- tree as the all external nodes linked to each other.
This statement is incorrect. Searching in a B+ tree is not harder than in a B- tree. In fact, B+ trees are often preferred over B- trees for database indexing because they allow for efficient traversal through all keys (all keys are stored in the leaves in a sorted manner and leaves are linked for easy traversal).
(D) In extendible hashing the size of directory is just an array of 2d-1, where d is global depth.
In extendible hashing, the size of the directory is not an array of 2d-1. It is actually an array of 2d, where 'd' stands for the global depth.
So, the correct answer from the options given is: 2) (A), (C) and (D) Only