from sqlalchemy import *
from migrate import *
from migrate.changeset import schema
meta = MetaData()

account = Table('account', meta,
Column('id', Integer(),  primary_key=True, nullable=False),
Column('login', String(length=40, convert_unicode=False, assert_unicode=None,unicode_error=None, _warn_on_bytestring=False)),
Column('passwd', String(length=40, convert_unicode=False, assert_unicode=None, unicode_error=None, _warn_on_bytestring=False)),)

def upgrade(migrate_engine):
    meta.bind = migrate_engine
    account.create()

def downgrade(migrate_engine):
     meta.bind = migrate_engine
     account.drop()

from sqlalchemy import *
meta = MetaData()
account = Table('account', meta,
Column('id', Integer(),  primary_key=True, nullable=False),
Column('login', String(length=None, convert_unicode=False, assert_unicode=None, unicode_error=None, _warn_on_bytestring=False)),
Column('passwd', String(length=None, convert_unicode=False, assert_unicode=None, unicode_error=None, _warn_on_bytestring=False)),
Column('newcol', String(length=None, convert_unicode=False, assert_unicode=None, unicode_error=None, _warn_on_bytestring=False)),)

from sqlalchemy import *
from migrate import *

from migrate.changeset import schema
meta = MetaData()
account = Table('account', meta,
  Column('id', Integer(),  primary_key=True, nullable=False),
  Column('login', String(length=None, convert_unicode=False, assert_unicode=None, unicode_error=None, _warn_on_bytestring=False)),
  Column('passwd', String(length=None, convert_unicode=False, assert_unicode=None, unicode_error=None, _warn_on_bytestring=False)),
)

def upgrade(migrate_engine):
    # Upgrade operations go here. Don't create your own engine; bind migrate_engine
    # to your metadata
    meta.bind = migrate_engine
    account.columns['newcol'].create()

def downgrade(migrate_engine):
    # Operations to reverse the above upgrade go here.
    meta.bind = migrate_engine
    account.columns['newcol'].drop()

Upgrading...
Traceback (most recent call last):
  File "./manage.py", line 3, in ?
    main(url='mysql://login:password@localhost/test_DB', debug='False', repository='.')
  File "/usr/lib/python2.4/site-packages/sqlalchemy_migrate-0.7.1-py2.4.egg/migrate/versioning/shell.py", line 207, in main
    ret = command_func(**kwargs)
  File "<string>", line 2, in test
  File "/usr/lib/python2.4/site-packages/sqlalchemy_migrate-0.7.1-py2.4.egg/migrate/versioning/util/__init__.py", line 159, in with_engine
    return f(*a, **kw)
  File "/usr/lib/python2.4/site-packages/sqlalchemy_migrate-0.7.1-py2.4.egg/migrate/versioning/api.py", line 219, in test
    script.run(engine, 1)
  File "/usr/lib/python2.4/site-packages/sqlalchemy_migrate-0.7.1-py2.4.egg/migrate/versioning/script/py.py", line 145, in run
    script_func(engine)
  File "/mnt/dev-mahmud/DL/RedIndigo/res/test-migrate/my_respository/002_migrate.py", line 16, in upgrade
    account.columns['newcol'].create()
  File "/usr/lib/python2.4/site-packages/SQLAlchemy-0.6.4-py2.4.egg/sqlalchemy/util.py", line 778, in __getitem__
    return self._data[key]
KeyError: 'newcol'