How SQLite Is Tested
2 days ago
- #Reliability
- #Testing
- #SQLite
- SQLite achieves reliability through thorough testing, with test code significantly exceeding the core code in size.
- Four main test harnesses are used: TCL Tests, TH3, SQL Logic Test (SLT), and dbsqlfuzz, each serving different testing purposes.
- TCL Tests are the original tests, providing millions of test cases during a full run, primarily used during development.
- TH3 offers 100% branch and MC/DC test coverage, designed for embedded systems without TCL support, running millions of test instances.
- SLT compares SQLite against other database engines like PostgreSQL and MySQL to ensure consistent query results.
- dbsqlfuzz is a proprietary fuzzer that mutates both SQL inputs and database files simultaneously to uncover new error states.
- Additional tests include anomaly tests for error handling, OOM and I/O error simulations, crash tests, and fuzz testing for invalid inputs.
- SQLite maintains 100% branch and MC/DC test coverage, verified through tools like gcov, and employs mutation testing to ensure test effectiveness.
- Dynamic analysis tools like Valgrind and custom memory and mutex checks are used to detect runtime errors and ensure thread safety.
- Static analysis and compiler warnings are monitored, though SQLite prioritizes extensive dynamic testing over static analysis for bug detection.
- A comprehensive release checklist ensures all tests pass before each release, with human review to catch subtle issues.