title: SQLiteOpenHelper, when is onCreate called
body: <p>I'm toying with the Android SDK, with a view to writting a simple app for friends (and maybe for sale).</p>
  
  <p>This app will search a database for keywords and dispaly the results on the screen, I've had a look at the searchabul dictonary and the notepad demo applications, but I'm still a bit unsure some things.</p>
  
  <p>I know I need to write a class that extends the SQLiteOpenHelper, and use that to create the database, however how do I check if the database already exists?</p>
  
  <p>Does onCreate get called on installation or every time an instance of the class is created? is the easyist way just to try and add the database each time and catch any errors (feels a little dangerous to be makeing the assumption every error will be due to the database already existing).</p>
  
  <p>Thanks in Advance.</p>