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 B+ Tree Index Files

 

B+ Tree Index is a multilevel index.

 

B+ Tree is a rooted tree satisfying the following properties :

 

  1.  All paths from the root to leaf are equally long.
  2.  If a node isn’t a root or a leaf, it has between [n / 2] and ‘n’ children.
  3.  A leaf node has between [(n-1) / 2] and ‘n-1’ values.

 The structure of any  node of this tree is :

Example- 1: Construct a B+ Tree for the following search key values, 

{10, 20, 30, 40 }

 where n = 3 ( n is number of pointers)

Example- 2: Construct a B+ Tree for the following search key values, Where n = 4. 

{10, 30, 40, 50, 60, 70, 90 }

Now, Let’s Insert and Delete some elements into this tree.

Insert 25,75

When we insert an element, we add it on the next right node of the value lower than the inserting element.

 

Delete 70

Here, when you delete any element. The element that has been deleted will be replaced with the element on the right.

 

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