title: BigInteger in SQLAlchemy or not?
body: <p>I apologize in advance if this is poorly formatted; it's rather late for me.</p>
  
  <p>Basically, I'm using Python with SQLAlchemy. I'm trying to map a class to a PostgreSQL DB table using the <a href="http://www.sqlalchemy.org/docs/orm/extensions/declarative.html#synopsis" rel="noreferrer">Object Relational Mapper, declarative style</a>.</p>
  
  <p>According to <a href="http://www.sqlalchemy.org/docs/core/types.html#generic-types" rel="noreferrer">SQLAlchemy's documentation on data types</a>, I should be able to use the type <code>BigInteger</code> to represent potentially large integers in the Database, particularly since I know that <a href="http://www.postgresql.org/docs/8.1/static/datatype.html#DATATYPE-INT" rel="noreferrer">PostgreSQL supports the BIGINT data type</a>.</p>
  
  <p>So, I attempt to declare my class like so:</p>
  
  <pre><code>import sqlalchemy
  from sqlalchemy import Column, BigInteger, Text, Sequence, Boolean
  from sqlalchemy.ext.declarative import declarative_base
  
  Base = declarative_base()
  
  class Account(Base):
      __tablename__ = 'accounts'
      __metadata__ = Base.metadata
  
      id = Column(BigInteger, Sequence('id_seq'), unique=True, nullable=False)
      email = Column(Text(32), unique=True, nullable=False)
  
      def __init__(self, email):
          self.email = email
  </code></pre>
  
  <p>However, when I try to use this file at all, I'm greeted with the following:</p>
  
  <pre><code>Traceback (most recent call last):
    File "sqltest02.py", line 9, in &lt;module&gt;
       from account import Account
    File "/home/pdusen/prog/account.py", line 2, in &lt;module&gt;
      from sqlalchemy import Column, BigInteger, Text, Sequence, Boolean
  ImportError: cannot import name BigInteger
  </code></pre>
  
  <p>So, according to SQLAlchemy's documentation, the <code>BigInteger</code> type exists, but according to python it does not. Is there something here I'm missing?</p>
  
  <p>Thanks in advance for all answers.</p>