The author demonstrates how to detect full table scans in SQLite using the `stat(:fullscan_steps)` API on prepared statements, offering a runtime alternative to `EXPLAIN`. This technique allows developers to automatically identify performance bottlenecks, such as missing indexes, which could be integrated into testing frameworks like Rails to fail tests when inefficient queries occur.
Background
Full table scans are a common cause of database performance degradation, typically resolved by adding appropriate indexes. While `EXPLAIN` is the standard tool for analyzing query plans, runtime statistics offer a programmatic way to monitor execution behavior dynamically.
- Source
- Lobsters
- Published
- Jul 16, 2026 at 07:57 AM
- Score
- 6.0 / 10