GATE CSE 2019 | Question: 14

Question

Which one of the following statements is NOT correct about the B+ tree data structure used for creating an index of a relational database table?

• A. B+ Tree is a height-balanced tree
• B. Non-leaf nodes have pointers to data records
• C. Key values in each node are kept in sorted order
• D. Each leaf node has a pointer to the next leaf node

Comments

B is the correct answer.

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No $\mathbf{B}$ is the wrong answer which is correct. :)

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B statement is wrong because it has written non-leaf nodes, if we make it leaf nodes then B is correct.

(only talking about the theory not the answer)

Answer 1

Properties of B+ trees:
1. B+ tree is height balance tree.
2. Key value is in sorted order.
3. Leaf node has pointer to next leaf node.
4. Non leaf node has pointer to a node (leaf or non leaf) and not pointer to data record.

Option B is not correct.

Comments

@Digvijay Pandey

is B tree also height balance tree??

as like B+ tree in B also all leaf are same node so B is also height balanced tree 

am I correct?

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@jlimbasiya, yes! you are correct, B-tree is also height balanced tree:)

Answer 2

Only leaf nodes have pointer for the data records, hence option B is not a property of a B+ tree.

Therefore, option B is correct answer.

Answer 3

Option B is correct

root node and internal node of  B + tree does not contain Data pointer/record pointer only leaf node will contain .

and in B tree root node , internal node as well as Leaf node will also contain Data Pointer .