django many to many releation ship, how to define migrations and create, and add them, dot walk

 offcial documentation:

https://docs.djangoproject.com/en/5.0/topics/db/examples/many_to_many/

from django.db import models


class Publication(models.Model):
    title = models.CharField(max_length=30)

    class Meta:
        ordering = ["title"]

    def __str__(self):
        return self.title


class Article(models.Model):
    headline = models.CharField(max_length=100)
    publications = models.ManyToManyField(Publication)

    class Meta:
        ordering = ["headline"]

    def __str__(self):
        return self.headline

>>> p1 = Publication(title="The Python Journal")

>>> p1.save()

 a1 = Article(headline="Django lets you build web apps easily")

a1.save()

a1.publications.add(p1)

//query

Article.objects.filter(publications=1)

-----------------------------------

DOT WALKING

>>> Publication.objects.filter(article__id=1)

>>> Publication.objects.filter(article__pk=1)Publication