title: SQLite3 OperationalError: Table XYZ has no column named ABC
body: <p>I am new to peewee, so please forgive me if this is a stupid question. I have searched on Google and in the peewee cookbook, but found no solution so far.</p>
  
  <p>So, I have the following models to four of my DB tables:</p>
  
  <pre><code>class games_def(Model):
      id = PrimaryKeyField()
      name = TextField()
      class Meta:
          database = dbmgr.DB
  
  class users_def(Model):
      id = PrimaryKeyField()
      first_name = TextField()
      last_name = TextField()
      class Meta:
          database = dbmgr.DB
  
  class sessions(Model):
      id = PrimaryKeyField()
      game = ForeignKeyField(games_def, related_name = 'sessions')
      user = ForeignKeyField(users_def, related_name = 'sessions')
      comment = TextField()
      class Meta:
          database = dbmgr.DB
  
  class world_states(Model):
      session = ForeignKeyField(sessions)
      time_step = IntegerField()
      world_state = TextField()
      class Meta:
          database = dbmgr.DB
  </code></pre>
  
  <p>Using these models I connect to an SQLite3 DB via peewee, which works fine.
  After the connection has been established I do the following in my main Python code:</p>
  
  <pre><code>models.world_states.create(session = 1, time_step = 1)
  </code></pre>
  
  <p>However, this gives me the following error:</p>
  
  <pre><code>sqlite3.OperationalError: table world_states has no column named session_id
  </code></pre>
  
  <p>That is basically correct, the table world_state does indeed not contain such a column.<br>
  However, I cannot find any reference to "session_id" in my code at all.</p>
  
  <p>Whe does peewee want to use that "session_id" colum name?<br>
  Do I miss something essentially here?</p>