title: django.db.utils.NotSupportedError in sqlite why not supported in sqlite
body: <pre><code>class M_Post(models.Model):
  ''''
  CODE
  ''''
  class M_File(models.Model):
  ....
  CODE
  ....
  
  class M_Post_File(models.Model):
      post = models.ForeignKey(M_Post,on_delete=models.CASCADE)
      file = models.ForeignKey(M_File,on_delete=models.CASCADE,null=True)
  </code></pre>
  
  <p>error:</p>
  
  <p>django.db.utils.NotSupportedError: Renaming the 'posts_file' table while in a transaction is not supported on SQLite because it would break referential integrity. Try adding <code>atomic = False</code> to the Migration class.</p>
  
  <p>how to solve this error</p>