title: Converting string to date timestamp in SQLAlchemy
body: <p>I have a database table, which I am accessing through SQLAlchemy. Each row is timestamped, but unfortunately it isn't simply a column with a DATE type.</p>
  
  <p>It is timestamped with two columns. One is the date <em>as a string</em> (not in the ISO format "YYYY-MM-DD" format, but in the Commonwealth "DD/MM/YYYY" format.) and the other is the time <em>as a string</em>.</p>
  
  <p>I could get the data into Python and convert it to a <code>datetime.datetime</code> with <code>strptime</code> but I want to filter the rows in SQL.</p>
  
  <p>How can I write SQL to do the equivalent of Python's strptime? - e.g. take the concatenated parts of a string and interpret it as a date? (I can figure <a href="http://www.w3schools.com/sql/sql_dates.asp" rel="nofollow">date->string</a>, but not string->date.)</p>
  
  <p>How can I persuade SQLAlchemy to generate that SQL?</p>