postgresql - Django ManyToMany reverse query with specific key -


i have 2 tables. first, basic user table. , second table called section.

def user(models.model):     ...     is_teacher = models.booleanfield(default=false)     ...  def section(models.model):     ...     teachers = models.manytomanyfield(user, related_name="teachers")     students = models.manytomanyfield(user, related_name="students")     is_active = models.booleanfield(default=true)     ...

i student users (identified in user table is_teacher=false) know can done user.objects.filter(is_teacher=false).

i also active section(s) each user.

but, @ moment, can't seem set of sections users.

i've tried:

students = user.objects.filter(is_teacher=false) s in students:     print s.section_set.all()

but i'm getting error user object has no section_set. i'm guessing because section has 2 many many relationships user table (teachers , students), have specify relationship more (to follow students 1 not teachers one). i'm not sure how this.

when defining related_name value, keep in mind name backwards relation (in case — user section). so, keep code clear , easy understand, i'd recommend change names this:

def section(models.model):     ...     teachers = models.manytomanyfield(user, related_name="sections_where_teacher")     students = models.manytomanyfield(user, related_name="sections_where_student")     is_active = models.booleanfield(default=true)     ...

then using relations looks this:

print s.sections_where_student.all()

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