You can view the source code of a tuning candidate as follows:

• On the Ad hoc SQL tab of the Input tab, you can see the SQL statements you typed or pasted into that tab.
• On the Database objects, SQL Files, and Active SQL in SGA tabs of the Input tab, you can double-click the name of any object added to that tab and an SQL session will open that displays the SQL of that database Object. The SQL editor in use is actually Rapid SQL, an IDERA product that is integrated with SQL Query Tuner.