ValueError: Attribute TweetSauceCache.sauce_index cannot be set to None

[sentry-io]

Sentry Issue: TWITTER-SAUCEBOT-3

ValueError: Attribute TweetSauceCache.sauce_index cannot be set to None
(5 additional frame(s) were not displayed)
...
  File "pony/orm/core.py", line 533, in new_func
    result = func(*args, **kwargs)
  File "twsaucenao/models/database.py", line 198, in set
    created_at=int(time.time())
  File "pony/orm/core.py", line 4712, in __init__
    avdict[attr] = attr.validate(val, obj, from_db=False)
  File "pony/orm/core.py", line 2194, in validate
    throw(ValueError, 'Attribute %s cannot be set to None' % attr)
  File "pony/utils/utils.py", line 106, in throw
    raise exc

[saucenaopls] An unknown error occurred while processing tweet 1388900095391846400

[rainyroads]

I thought I had addressed this manually by altering the table column on the server to be nullable, but it's still occurring.