B-tree index structure in DBMS Theory - Mini Project: Build & Apply

Build a Simple B-tree Index Structure

📖 Scenario: You are working on a small database system that needs to quickly find records by their keys. To do this, you will build a simple B-tree index structure step-by-step.

🎯 Goal: Build a basic B-tree index structure with nodes and keys, add a configuration for the maximum number of keys per node, insert keys into the tree, and complete the tree structure.

📋 What You'll Learn

Create a B-tree node data structure with keys and children

Add a configuration variable for maximum keys per node

Implement insertion of keys into the B-tree node

Complete the B-tree structure by linking nodes properly

💡 Why This Matters

🌍 Real World

B-trees are used in databases and file systems to quickly find and store data by keys.

💼 Career

Understanding B-tree structures helps in database design, optimization, and working with indexing systems.

1

Create the B-tree node data structure

Create a class called BTreeNode with two attributes: keys as an empty list and children as an empty list.

DBMS Theory

# Create the BTreeNode class with keys and children attributes
# Your code here

Need a hint?

Think of a B-tree node as a box that holds keys and pointers to child nodes.

2

Add maximum keys per node configuration

Create a variable called max_keys and set it to 3 to limit the number of keys each B-tree node can hold.

DBMS Theory

class BTreeNode:
    def __init__(self):
        self.keys = []
        self.children = []

# Set the maximum number of keys per node
# Your code here

Need a hint?

This variable controls how many keys a node can hold before splitting.

3

Implement key insertion into B-tree node

Add a method called insert_key to the BTreeNode class that takes a parameter key and inserts it into the keys list in sorted order.

DBMS Theory

class BTreeNode:
    def __init__(self):
        self.keys = []
        self.children = []

    # Insert a key into the keys list in sorted order
    # Your code here

max_keys = 3

Need a hint?

Insert the key and then sort the list to keep keys ordered.

4

Complete the B-tree structure by linking nodes

Create a root node called root as an instance of BTreeNode. Insert the keys 10, 20, and 5 into root using the insert_key method.

DBMS Theory

class BTreeNode:
    def __init__(self):
        self.keys = []
        self.children = []

    def insert_key(self, key):
        self.keys.append(key)
        self.keys.sort()

max_keys = 3

# Create root node and insert keys 10, 20, 5
# Your code here

Need a hint?

Use the insert_key method to add keys to the root node.