EE 441 Data Structures Btrees example

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EE 441 Data StructuresBtrees example
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BTree Example
Insert 55 find
45
50
55
50
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BTree Example
Insert 55 insert at leaf node Node is too big
45
50
55
50
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BTree Example
Insert 55 move up middle key and insert
45
50
55
50
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BTree Example
Insert 55 Split the big node fix the links
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BTree Example
Inserted 55 Insert 37 Find
35
37
38
37
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BTree Example
Insert 37 insert at leaf node Node is too big
35
37
38
37
40
50
37
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BTree Example
37
40
50
Insert 55 move up middle key 37 Node is too big
35
37
38
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BTree Example
Insert 37 move up middle key 40 and insert
37
40
50
35
37
38
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BTree Example
Insert 37 split first big node (starting from
the root) and fix the links
35
37
38
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BTree Example
Insert 37 split next big node and fix the links
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BTree Notes

• Insertion at a node with free available space for
  a key Insert the key at the right place and
  rearrange the node and sub-trees if required
• Start insertion from the leaf level
• Keep generating big nodes and extract the middle
  key of the big node to push it up towards the
  root
• Keep the big nodes without splitting and keep
  propagating to the upper levels
• Mid key might appear more than once during this
  process
• When the last push-up operation is completed,
  start splitting the nodes and moving down