SQLAlchemy bug? I'm not sure

from sqlalchemy import create_engine
from sqlalchemy import Table, Column, Integer, String, MetaData, ForeignKey
from sqlalchemy.orm import mapper, sessionmaker
from sqlalchemy.ext.declarative import declarative_base

from bottle import route, post, get, request
import os

Base = declarative_base()

class User(Base):
    """Table for login details"""
    __tablename__ = 'login_table'
    id = Column(Integer, primary_key=True)
    username =  Column(String)
    password =  Column(String)
    email = Column(String)

    def __init__(self, username, password, email):
        """Create a object containing info of a user"""
        self.username = username
        self.password = password
        self.email = email

    def __str__(self):
        """Return a string representation"""
        return self.username

    def __repr__(self):
        """Return a object representation"""
        return "<User(%s)>" % self.username

def force_engine():
    engine = create_engine('sqlite:///users.db', echo=True)
    Base.metadata.create_all(engine)
    Session = sessionmaker()
    Session.configure(bind=engine)
    session = Session()
    session.commit()

def spawn_session():
    engine = create_engine('sqlite:///users.db')
    Session = sessionmaker()
    Session.configure(bind=engine)
    return Session()

def create_user(username, password, email):
    session = spawn_session()
    session.add(User(username, password, email))
    session.commit()
    return True

def register_test():
    create_user('dave','test', 'a')
    create_user('cat','123','a')

if not os.path.exists('users.db'):
    force_engine()

@get('/register')
def register_form():
    return '''<form method="POST">
                <p>Welcome new user. Enter a username, password, email.</p></br>
                <p>Username: </p><input name="username" type="text" /></br>
                <p>Password: </p><input name="password" type="password" /></br>
                <p>Email: </p><input name="email" type="text" /></br>
                <input type="submit" value="Submit" />
              </from>'''

@post('/register')
def register_submit():
    name     = request.forms.get('username')
    password = request.forms.get('password')
    email = request.forms.get('email')
    authd = create_user(name, password, email)
    if authd:
        return "<p>User created</p>"
    else:
        return "<p>Failure</p>"

This is the code I'm using. Don't tell me about security, or anything else. Just help me figure out why its causing this traceback

>>> register_test()
Traceback (most recent call last):
  File "<interactive input>", line 1, in <module>
  File "C:\Users\Public\Documents\webapps\login\register.py", line 54, in register_test
    create_user('dave','test', 'a')
  File "C:\Users\Public\Documents\webapps\login\register.py", line 50, in create_user
    session.commit()
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\orm\session.py", line 623, in commit
    self.transaction.commit()
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\orm\session.py", line 385, in commit
    self._prepare_impl()
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\orm\session.py", line 369, in _prepare_impl
    self.session.flush()
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\orm\session.py", line 1397, in flush
    self._flush(objects)
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\orm\session.py", line 1478, in _flush
   开发者_如何转开发 flush_context.execute()
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\orm\unitofwork.py", line 304, in execute
    rec.execute(self)
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\orm\unitofwork.py", line 448, in execute
    uow
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\orm\mapper.py", line 1872, in _save_obj
    execute(statement, params)
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\engine\base.py", line 1191, in execute
    params)
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\engine\base.py", line 1271, in _execute_clauseelement
    return self.__execute_context(context)
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\engine\base.py", line 1302, in __execute_context
    context.parameters[0], context=context)
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\engine\base.py", line 1401, in _cursor_execute
    context)
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\engine\base.py", line 1394, in _cursor_execute
    context)
  File "C:\Python26\lib\site-packages\sqlalchemy-0.6.5-py2.6.egg\sqlalchemy\engine\default.py", line 299, in do_execute
    cursor.execute(statement, parameters)
OperationalError: (OperationalError) table login_table has no column named email u'INSERT INTO login_table (username, password, email) VALUES (?, ?, ?)' ('dave', 'test', 'a')

Even when I close down python entirely, and delete the database entirely I still get the same execption

Very nice write up here about using SQLAlchemy and SQLite in this tutorial

You need to verify that you are on at least version 0.7 of SQLAlchemy

>>> import sqlalchemy
>>> sqlalchemy.__version__ 
0.7.0

use echo to display the SQL generated

>>> from sqlalchemy import create_engine
>>> engine = create_engine('sqlite:///users.db', echo=True)

and you might have missed this very important step

>>> from sqlalchemy.ext.declarative import declarative_base
>>> Base = declarative_base()

finally verify that you have created the table correctly

>>> User.__table__ 
Table('users', MetaData(None),
            Column('id', Integer(), table=<users>, primary_key=True, nullable=False),
            Column('name', String(), table=<users>),
            Column('username', String(), table=<users>),
            Column('password', String(), table=<users>), 
            Column('email', String(), table=<users>), schema=None)