To do this, the extract will need to be recreated and published. However, using the replace data source option will allow you to switch out the data source in your workbook so that the entire workbook doesn't need to be recreated.
Thanks Tracy. Is the best practice to save the custom sql for the data source so the extract can be recreated or to save the custom sql as a data source?
Alternatively, can an extract be based on a sql server Stored Procedure or View so that editing can happen on the sql server side?