## Discussion Forum

Que. | A B+ tree index is to be built on the name attribute of the relation STUDENT. Assume that all students names are of length 8 bytes, disk block are of size 512 bytes and index pointers are of size 4 bytes. Given this scenario what would be the best choice of the degree (i.e. the number of pointers per node) of the B+ tree ? |

a. | 16 |

b. | 42 |

c. | 43 |

d. | 44 |

Answer:16 |

SUBHAJIT PAL :(January 31, 2018)
Answer: C
In a B+ tree we want en entire node content to be in a disk block. A node can contain up to p pointers to child nodes and up to N−1 key values for a B+ tree of order N. Here, key size is 8 bytes and pointer size is 4 bytes. Thus we can write 8(p−1)+4p≤512⟹12p≤520⟹p=43. |

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