跨關係查詢:
模型:
class Grade(models.Model):
g_name = models.CharField(max_length=16)
class Student(models.Model):
s_name = models.CharField(max_length=16)
s_grade = models.ForeignKey(Grade)
使用:
模型類名__屬性名__比較運算符,實際上就是處理的數據庫中的join
Grade —g_name Student—》s_name s_grade(外鍵)
gf = Student.objects.filter(name='鳳姐')
print(gf[0].s_grade.name)
grades = Grade.objects.filter(student__s_name='Jack')
查詢jack所在的班級