Values in field which is used as primary key should be unique.
A primary key is used to uniquely identify each record in the Model's database table.
A non-unique primary key allows the same value to be used for multiple records. Therefore, multiple objects can exist with the same primary key, which might not be something that was intended.
primary_key=True denotes that the field is a primary key for the model.
It implicitly means
unique=False is not recommended.
class MyModel(models.Model): my_field = models.CharField( primary_key=True, unique=False )
class MyModel(models.Model): my_field = models.CharField(primary_key=True)