title: SqlAlchemy: How to make a LONGBLOB column in mysql?
body: <p>Using sqlalchemy with mysql-python, I have this table:</p>
  
  <pre><code>from sqlalchemy.ext.declarative import declarative_base
  from sqlalchemy import Column, Index, LargeBinary
  Base = declarative_base()
  class Tbl(Base):
       __tablename__ = 'tbl'
       ...
       data = Column(LargeBinary())
  </code></pre>
  
  <p>However, when I create this table (using <code>Base.metadata.create_all(engine)</code>), and then <code>DESCRIBE tbl;</code> in mysql, I get this:</p>
  
  <pre><code>mysql&gt; describe logs;
  +--------------+-------------+------+-----+---------+----------------+
  | Field        | Type        | Null | Key | Default | Extra          |
  +--------------+-------------+------+-----+---------+----------------+
  ...
  | data         | blob        | YES  |     | NULL    |                |
  +--------------+-------------+------+-----+---------+----------------+
  </code></pre>
  
  <p>Expected result: I want this to be a <code>longblob</code> in mysql, and not a <code>blob</code> which is limited to 64kB</p>