b trees
Post on 14-Jun-2015
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B Trees
Sample B tree
• Minimization Factor : No of allowable Children for each node
• every node must have at least t - 1 keys
• Every node may have at most 2t - 1
• the height of an n-key b-tree
With t greater than or equal to 2,
Sample B tree
B-tree of order 5
all internal nodes have at least ceil(5 / 2) = ceil(2.5) = 3 children
maximum number of children that a node can have is 5
Insertion
• B-tree of order 5:
C N G A H E K Q M F W L T Z D P R X Y S
Order 5 means that a node can have a maximum of 5 children and 4 keys.
All nodes other than the root must have a minimum of 2 keys.
• C N G A Order this ACGN
• Inserting ACGN
Inserting H
Inserting E, K, and Q proceeds without requiring any splits:
Inserting M requires a split
The letters F, W, L, and T are then added without
needing any split
Adding Z
Inserting D
Inserting s
DELETION (H)
Delete T
Delete R
Delete E
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