Bloom Filters: The Secret to Making SQLite 10x Faster

Researchers cleverly used Bloom filters to make SQLite analytical queries 10x faster. They discovered that SQLite's nested loop joins were inefficient, with much time spent on B-tree probes. By using a Bloom filter before the join operation to quickly filter out rows unlikely to match, and then performing B-tree probes only on potential matches, the number of probes was significantly reduced. Bloom filters have minimal memory overhead and were easy to integrate into SQLite's existing query engine, resulting in a significant performance boost. This improvement has been integrated into SQLite v3.38.0.