Which of the following statements is/are NOT CORRECT?
(A) The first record in each block of the data file is known as the actor record.
(B) A dense index has index entries for every search-key value in the data file.
(C) Searching is harder in a B+ tree than in a B-tree as all external nodes are linked to each other.
(D) In extendible hashing, the size of the directory is 2^(d−1), where d is the global depth.
Choose the correct answer from the options given below:
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Correct answer: B. (A), (C) and (D) Only
Explanation
The first record of a block is the anchor record (A wrong). B is correct. Linked leaves make range searching easier in B+ trees (C wrong). The directory size is 2^d (D wrong).More Database Management Systems questions
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