How to fix Assert failure in PostgreSQL

Look at the PostgreSQL log file to find the complete assert failure message and stack trace. This provides crucial context about where the failure occurred.

tail -100 /var/log/postgresql/postgresql-*.log
# Or check the data directory
tail -100 /path/to/pgdata/log/postgresql-*.log

Note the exact assertion that failed, the function name, and line number.

Assert failures may be caused by bugs fixed in newer minor versions. Update to the latest stable release in your major version branch.

# On Ubuntu/Debian
sudo apt-get update
sudo apt-get upgrade postgresql-14  # Replace 14 with your version

# Then restart PostgreSQL
sudo systemctl restart postgresql

Always test updates on a non-production environment first.

Third-party extensions can cause assert failures. Test if the issue persists without extensions.

-- List installed extensions
SELECT * FROM pg_extension;

-- Disable extensions one at a time
DROP EXTENSION IF EXISTS extension_name CASCADE;

-- After dropping, run the operation that caused the failure

If the error disappears after disabling an extension, that extension is the culprit. Update or replace it.

Memory corruption and disk errors are common causes of assert failures. Run hardware tests to rule them out.

# Test RAM using memtest86+
boot into memtest86+
# Let it run for at least 8+ hours

# Check disk health
sudo smartctl -a /dev/sda  # Replace with your disk

# Check system logs for hardware errors
sudo dmesg | grep -i error

If hardware issues are found, contact your infrastructure provider or hardware vendor.

If hardware is fine but assert failures continue, check for data corruption.

# Stop PostgreSQL
sudo systemctl stop postgresql

# Run pg_filedump to inspect table structures (careful with production)
pg_filedump /path/to/pgdata/base/your_database_oid/table_oid

# Restart and consider reindexing
sudo systemctl start postgresql

-- Reindex problematic tables
REINDEX TABLE table_name;

-- Analyze to update statistics
ANALYZE table_name;

If you can reliably reproduce the assert failure and suspect a PostgreSQL bug, report it to the PostgreSQL mailing list.

1. Gather information:
- PostgreSQL version: SELECT version();
- Operating system and version
- Complete error message and stack trace from logs
- Steps to reproduce

2. Post to [email protected] with clear details

3. PostgreSQL developers may request a core dump or additional debugging information to help fix the issue.