# Topic covered
* Django default User Model
* Custom User Model
* AbstractUser vs AbstractBaseUser
* Validating objects
* full_clean()
* Model.clean_fields()
* Model.clean()
* Model.validate_unique()
01-Django ORM Introduction
Django ORM Introduction
1. Django ORM
The Django web framework includes a default object-relational mapping layer (ORM) that can be used to interact with
various relational databases such as SQLite, PostgreSQL, and MySQL. It allows us to add, delete, modify, and query objects.
An object-relational mapper provides an object-oriented layer between relational databases and
object-oriented programming languages without having to write SQL queries.
02-Django ORM Relationship
Django ORM Relationship
Relationship
Django supports relational databases and allows us to establish relations between different models.
There are three types of relational fields which Django supports: many-to-one, many-to-many and one-to-one.