Build a Practical Models, Migrations, and the ORM Example in Django Web Development

Define the build target

For Models, Migrations, and the ORM, design two related tables or models, add constraints, and create a migration that can be applied to a test database. Build the boundary case using this implementation lens: Use Django URL routing, views, templates, ORM models, forms, authentication, class-based architecture, tests, settings, and deployment behavior.

Keep the Models, Migrations, and the ORM build centered on these technical constraints: Primary keys. Foreign keys and cardinality. Apply them through this path lens: Use Django URL routing, views, templates, ORM models, forms, authentication, class-based architecture, tests, settings, and deployment behavior. Use Django URL routing, views, templates, ORM models, forms, authentication, class-based architecture, tests, settings, and deployment behavior.

Implement the core behavior

Implement Models, Migrations, and the ORM around the module artifact—a working models, migrations, and the orm example with an explicit success and failure check—and keep the implementation specific to this path context: Use Django URL routing, views, templates, ORM models, forms, authentication, class-based architecture, tests, settings, and deployment behavior.

CREATE TABLE customers (
  id bigint GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
  email text NOT NULL UNIQUE
);

CREATE TABLE orders (
  id bigint GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
  customer_id bigint NOT NULL REFERENCES customers(id),
  total numeric(10,2) NOT NULL CHECK (total >= 0)
);

psql -f schema.sql

The database rejects duplicate customer emails, missing customers, and negative order totals.

practice/\n├── README.md\n├── models-migrations-and-the-orm-build.sql\n└── evidence/\n    └── expected-result.txt

Run the complete path

Run one realistic Models, Migrations, and the ORM case end to end and record the required evidence: the relevant output, test, log, query result, or rendered state for Models, Migrations, and the ORM. Interpret the result through this path context: Use Django URL routing, views, templates, ORM models, forms, authentication, class-based architecture, tests, settings, and deployment behavior.

Change one meaningful condition

Modify one condition central to Models, Migrations, and the ORM using this path context: Use Django URL routing, views, templates, ORM models, forms, authentication, class-based architecture, tests, settings, and deployment behavior. Predict the new result before rerunning the same workflow.

Verify the artifact

Your deliverable is a working models, migrations, and the orm example with an explicit success and failure check.

Common mistakes to avoid

• Relationship cardinality wrong.
• Constraint missing from database.
• Destructive migration without backfill.
• Duplicate data violates new constraint.