Database Index Explorer — Interactive System Design Lab

Insert records and toggle a B-tree index on or off to see read and write performance change. Without an index, every query scans the full table O(n). With one, the engine walks a tree in O(log n). The write overhead of maintaining the index is also visible — the classic read-write tradeoff.

Visualise how B-tree indexes speed up reads at the cost of writes.

This free interactive simulation runs directly in your browser — no account needed. Adjust the parameters and watch how the system responds in real time.

Concepts covered

• database index
• B-tree
• full table scan
• query plan
• compound index
• database performance

Read the guide

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