title: sqlalchemy-migrate DatabaseNotControlledError exception
body: <p>I would like to add a new column in my existing database, initially created by <code>sqlalchemy</code>.</p>
  
  <p>I tried using the <code>sqlalchemy-migrate</code> tool to do this and running into the following error:</p>
  
  <pre><code>C:\Users\sk11\Desktop\playground\migrateDB&gt;%PYTHON_EXE% manage.py db_version
  Traceback (most recent call last):
    File "manage.py", line 5, in &lt;module&gt;
      main(url='sqlite:///Results.db', debug='False', repository='sdb')
    File "C:\Python27\lib\site-packages\sqlalchemy_migrate-0.7.2-py2.7.egg\migrate\versioning\shell.py", line 207, in main
      ret = command_func(**kwargs)
    File "&lt;string&gt;", line 2, in db_version
    File "C:\Python27\lib\site-packages\sqlalchemy_migrate-0.7.2-py2.7.egg\migrate\versioning\util\__init__.py", line 159, in with_engine
      return f(*a, **kw)
    File "C:\Python27\lib\site-packages\sqlalchemy_migrate-0.7.2-py2.7.egg\migrate\versioning\api.py", line 148, in db_version
      schema = ControlledSchema(engine, repository)
    File "C:\Python27\lib\site-packages\sqlalchemy_migrate-0.7.2-py2.7.egg\migrate\versioning\schema.py", line 32, in __init__
      self.load()
    File "C:\Python27\lib\site-packages\sqlalchemy_migrate-0.7.2-py2.7.egg\migrate\versioning\schema.py", line 44, in load
      self.table = Table(tname, self.meta, autoload=True)
    File "build\bdist.win32\egg\sqlalchemy\schema.py", line 318, in __new__
    File "build\bdist.win32\egg\sqlalchemy\schema.py", line 381, in _init
    File "build\bdist.win32\egg\sqlalchemy\schema.py", line 408, in _autoload
    File "build\bdist.win32\egg\sqlalchemy\engine\base.py", line 2426, in run_callable
    File "build\bdist.win32\egg\sqlalchemy\engine\base.py", line 1969, in run_callable
    File "build\bdist.win32\egg\sqlalchemy\engine\default.py", line 260, in reflecttable
    File "build\bdist.win32\egg\sqlalchemy\engine\reflection.py", line 412, in reflecttable
  migrate.exceptions.DatabaseNotControlledError: migrate_version
  </code></pre>
  
  <p>I followed exactly the same steps as explained in the <a href="https://sqlalchemy-migrate.readthedocs.org/en/latest/versioning.html" rel="nofollow">docs</a>. Before checking for <code>db_version</code> (for which I am getting the above error) I tried <code>version</code> command which worked fine.</p>
  
  <pre><code>C:\Users\sk11\Desktop\playground\migrateDB&gt;C:\Python27\Scripts\migrate.exe manage manage.py --repository=sdb --url=sqlite:///Results.db
  
  C:\Users\sk11\Desktop\playground\migrateDB&gt;%PYTHON_EXE% manage.py version
  0
  </code></pre>
  
  <p>Any ideas where to look further or what I am doing wrong?</p>