title: sqlite - creating an audit using triggers
body: <p>I would like to create a little auditing mechanism for my tables in sqlite where any time a change is made to a table, i update 2 fields that show who changed the data and when. 
  We use a similar concept in our MS SQL Server databases.
  But I'm wondering how I could implement this in sqlite.  I've added 2 fields to the end of my table called updatedusername, and a updateddatetime field. 
  When end users sign into my web application and make changes, i can "insert" the user credentials along with any other data for the specific table... 
  But i'm wondering how i could accomplish the same thing with triggers. 
  Can anyone shed some light on this?<br>
  For example, if i were to set up a trigger, when a new record is inserted or existing data is updated, how would I supply the username of the person that logged into the app to make the change, instead of some generic web id that's being used by my server....</p>
  
  <p>Thanks. </p>