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python - Django - syncdb doesn't create tables

I added a many-to-many field to an existing model and was expecting syncdb to create a new table, but there's nothing there. This is what the model looks like:

class Author(models.Model):
    first_name = models.CharField(max_length=50)
    last_name = models.CharField(max_length=50)
    email = models.EmailField()

    def __unicode__(self):
        return "{0} {1}".format(self.first_name, self.last_name)

class Book(models.Model):
    title = models.CharField(max_length=100)
    authors = models.ManyToManyField(Author)

    def __unicode__(self):
        return self.title

Running sql myapp prints the correct statements with the new table, but this is not reflected when I run syncdb. validate also returns no errors. Does anyone know what could be the matter here? Or a better diagnostic?

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The syncdb command does not create many to many tables for existing models by design. This decision is explained on ticket 2229.

That leaves you with a few options.

  • If you don't have any data in your Book model, drop the table and rerun syncdb. Django will recreate the book table and the many to many table.
  • Use the dbshell command, and create the many to many joining table using the output of sql myapp.
  • If you're doing multiple schema migrations with Django, make friends with South.

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