title: SqlAlchemy "too many clients already" error
body: <p>I'm fairly new to python and pyramid framework. Recently I was introduced to SQLSoup to take care of my database (postgres) needs. </p>
  
  <pre><code>dbEngine1 = SqlSoup(settings['sqlalchemy.db1.url'])
  users = dbEngine1.users.fetchall()
  </code></pre>
  
  <p>Everything is working great, however after a short period of using the pyramid app, I'm getting this error message. I have to kill pyramid to release all idling connections in postgres (about 50 idling connection before throwing below exception)</p>
  
  <pre><code>sorry, too many clients already
  </code></pre>
  
  <p>My question is, how do I close this idling connection, I tried adding a line of code as shown below, but it does not help.</p>
  
  <pre><code>dbEngine1 = SqlSoup(settings['sqlalchemy.db1.url'])
  users = dbEngine1.users.fetchall()
  dbEngine1.engine.connect().close()
  </code></pre>
  
  <p>Any pointer from SQLAlchemy gurus?</p>