4. How to add a database view to Django admin?

You have a database view, created as this:

create view entities_entity as
    select id, name from entities_hero
    union
    select 10000+id as id, name from entities_villain

It has all the names from Hero and Villain. The id’s for Villain are set to 10000+id as id because we don’t intend to cross 10000 Heroes:

sqlite> select * from entities_entity;
1|Krishna
2|Vishnu
3|Achilles
4|Thor
5|Zeus
6|Athena
7|Apollo
10001|Ravana
10002|Fenrir

Then you add a managed=False model:

class AllEntity(models.Model):
    name = models.CharField(max_length=100)

    class Meta:
        managed = False
        db_table = "entities_entity"

And add it to admin.:

@admin.register(AllEntity)
class AllEntiryAdmin(admin.ModelAdmin):
    list_display = ("id", "name")

And your admin looks like this