After creating a configuration analysis, you can add more SQL statements from the SQL Repository to it.
To add SQL to an existing configuration analysis
From the left pane, select the analysis in which you want to add the SQL.
Right-click and select Add SQL.
From the Add SQL window under the Select SQL to be added pane, check the SQL statements you want added.
Under the Select Scenario to include SQL pane, check the Scenarios you want the SQL added to.
Click OK to add the SQL, retrieve the query plans and re-execute the Scenario.