SQL Invariants

Verify database-level guarantees.

Example


checkType: sql
says: "No orphaned orders"
steps:
  - sql:
      query: |
        SELECT COUNT(*) as count
        FROM orders
        WHERE customer_id NOT IN (SELECT id FROM customers)
      url_env: "DATABASE_URL"
    expect:
      rows:
        - count: 0

Store your connection string in Settings → Secrets.

Common Patterns

Referential integrity:


SELECT COUNT(*) FROM order_items oi
LEFT JOIN products p ON oi.product_id = p.id
WHERE p.id IS NULL

Business rules:


SELECT COUNT(*) FROM inventory WHERE quantity < 0

Read-Only Access

Use a read-only database user:


CREATE USER stoney_readonly WITH PASSWORD '...';
GRANT SELECT ON ALL TABLES IN SCHEMA public TO stoney_readonly;

Supported Databases

PostgreSQL, MySQL, SQLite, SQL Server