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SQL (SQLite engine)

Test a foreign key constraint

Medium70 pts~25 min
  • Foreign keys
  • Negative testing
Practice app · Acme Commerce DB

A real SQL database (SQLite engine) seeded with an e-commerce and HR dataset, with schema browser and query runner.

Test URL
/lab/database-testing-test-a-foreign-key-constraint

Your starter code already declares TEST_URL — never hardcode a host.

Objective

Verify orders and order_items reject references to parents that do not exist.

Your task

  1. 1Insert an order for customer_id 999 (order_date '2025-12-30', status 'pending', total 10); it must fail.
  2. 2Insert an order_items row for order 1 with product_id 999; it must fail too.
  3. 3Verify nothing was stored: SELECT (SELECT COUNT(*) FROM orders) AS orders, (SELECT COUNT(*) FROM order_items) AS order_items.

Acceptance criteria

  • An insert fails with FOREIGN KEY constraint failed
  • The last result set shows the original counts (60 orders, 150 items)

Constraints

  • Every run starts from a freshly seeded database, so your script must include its own setup statements.
  • A failing statement is recorded and the script keeps running, so you can trigger an error and verify afterwards.
  • Only the last result set of your script is compared, so finish with the verification query.

SQL (SQLite engine) · Database Testing · Constraints & keys