将 SQL 查询集转换为 Django Model 查询集

Question

I need a little help, I come from working with relational data models and now I venture into Django Framework, I need to make an API that returns something like this SQL query

SELECT user_profile_userprofile.email,
     user_profile_userprofile.name,
     business_unity.active AS status,
     profile.name AS profile,
     business_unity.name AS unit

FROM user_profile_userprofile
      JOIN profile ON user_profile_userprofile.id = profile.id
      JOIN user_profile_unity ON user_profile_unity.user_id = user_profile_userprofile.id
      JOIN business_unity ON user_profile_unity.id = business_unity.id;

The models are already created but I don't know how to make a view in python that meets the conditions of this query

Answer 1

Basically, you need to "preload" the associations using select_related , and then you just use the normal methods to navigate them.

Assuming your models are something like

class UserProfile(Model):
    profile = ForeignKey("Profiles", ...)
    unity = ForeignKey("Unity", ...)

class Unity(Model):
    business_unity = ForeignKey("business.Unity", ...)

qs = UserProfile.select_related("profile", "unity__business_unity").all()
up = qs[0]

Now you have all your data loaded (and more)

print(up.email)
print(up.name)
print(up.unity.business_unity.active)
print(up.profile.name)
print(up.unity.business_unity.name)