將 SQL 查詢集轉換為 Django Model 查詢集

Question

我需要一點幫助，我來自使用關系數據模型，現在我冒險進入 Django 框架，我需要創建一個 API 來返回類似這樣的 SQL 查詢

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;

模型已經創建，但我不知道如何在 python 中創建滿足此查詢條件的視圖

Answer 1

基本上，您需要使用select_related來“預加載”關聯，然后您只需使用常規方法來導航它們。

假設您的模型類似於

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]

現在您已加載所有數據（以及更多）

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