Index Performance Visualizer

Overview

The Index Performance Visualizer demonstrates the dramatic speed difference between full table scans and indexed lookups through interactive simulation. Adjust the table size and watch how query performance changes with and without indexes, seeing the contrast between O(n) linear scans and O(log n) B-tree lookups. Essential for understanding when and why to add database indexes.

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Tips

  • Test with small datasets (100-1000 rows) first to see minimal differences, then increase to 10,000+ rows to see indexes shine
  • Notice how the performance gap widens exponentially as table size grows - this is why indexes are critical for production databases
  • Remember that indexes speed up SELECT queries but add overhead to INSERT, UPDATE, and DELETE operations
  • The logarithmic scaling of B-tree indexes means doubling your data only adds one additional lookup step
  • Don’t index every column - each index consumes disk space and slows down writes, so focus on columns in WHERE, JOIN, and ORDER BY clauses
  • For small lookup tables (< 1000 rows), the overhead of maintaining an index may outweigh its benefits
  • Use this visualization when explaining to stakeholders why query optimization through indexing is worth the investment