changing django default model settings

I'm just starting with the django creating your own app tutorial (creating a Poll) I'm deviating slightly as I'm wanting to create an app using my own database model that already exists.

And in the tutorial it says

• Table names are automatically generated by combining the name of the app (polls) and the lowercase name of the model -- poll and choice. (You can override this behavior.)
• Primary keys (IDs) are added automatically. (You can override this, too.)
• By convention, Django appends "_id" to the foreign key field name. Yes, you can override this, as well.

But I can't see where it mentions how you can override this behaviour? I've defined my model as so

from django.db import models

# Create your models here.
class Channels(models.Model):
    channelid = models.IntegerField()
    channelid.primary_key = True
    channelname = models.CharField(max_length=50)

Now when I go in to the shell this is what I get

>>> from tvlistings.models import *
>>> Channels.objects.all()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "C:\Python26\lib\site-packages\django\db\models\query.py", line 67, in __
repr__
    data = list(self[:REPR_OUTPUT_SIZE + 1])
  File "C:\Python26\lib\site-packages\django\db\models\query.py", line 82, in __
len__
    self._result_cache.extend(list(self._iter))
  File "C:\Python26\lib\site-packages\django\db\models\query.py", line 271, in i
terator
    for row in compiler.results_iter():
  File "C:\Python26\lib\site-packages\django\db\models\sql\compiler.py", line 67
7, in results_iter
    for rows in self.execute_sql(MULTI):
  File "C:\Python26\lib\site-packages\django\db\models\sql\compiler.py", line 73
2, in execute_sql
    cursor.execute(sql, params)
  File "C:\Python26\lib\site-packages\django\db\backends\util.py", line 15, in e
xecute
    return self.cursor.execute(sql, params)
  File "C:\Python26\lib\site-packages\django\db\backends\mysql\base.py", line 86
, in execute
    return self.cursor.execute(query, args)
  File "C:\Python26\lib\site-packages\MySQLdb\cursors.py", line 166, in execute
    self.errorhandler(self, exc, value)
  File "C:\Python26\lib\site-packages\MySQLdb\connections.py", line 35, in defau
lterrorhandler
    raise errorclass, errorvalue
DatabaseError: (1146, "Table 'tvlistings.tvlistings_channels' doesn't exist")

Obviously it can't find the table tvlistings_channels as it's actually called channels. So how do I change the default?

You can override Model behavior in Django largely through the use of an inner Meta class

• db_table allows you to rename the table name
• specifying another field as the primary key will have it use that rather than a surrogate key (not in the Meta class, just in the model itself)