December 2018
Beginner to intermediate
796 pages
19h 54m
English
Content preview from Learn Web Development with Python
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Defining unique constraints
The RESTful Web Service doesn't use any constraints, and therefore, it is possible to create many drone categories with the same name. We don't want to have many drone categories with the same name. Each drone category name must be unique in the database table that persists drone categories (the drones_dronecategory table). We also want drones and pilots to have unique names. Hence, we will make the necessary changes to add unique constraints to each of the following fields:
- The name field of the DroneCategory model
- The name field of the Drone model
- The name field of the Pilot model
We will learn the necessary steps to edit existing models and add constraints to fields that are already persisted in tables and ...
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