For building ad-hoc reports by using new data model user should have BI Administrator role.
From the navigator, click on the ‘Build a Report’ link. If the My Reporting link is not visible look for it under... (Navigation is: Navigator > My Reporting > Build a Report)
The Reports and Analytics screen will open up. On this screen, find the Create button drop-down and click on the Report
Once you’ve clicked the Report option, a new Oracle Business Intelligence Create Report window will open (Check for popups if the new window does not open)
On the Business Intelligence page, use the option to create a new ‘Data Model.’
From the Data model page, select the SQL query as the object.
On the New Data Set – enter the required field and write your SQL in the Query section.
Save the Data Model by clicking on the Save icon. Preferably create a folder for your implementation and use it to save the data model.
Once you’ve saved the data model, you will notice that the data model is selected. Now click on the Generate icon to generate the RTF layout based on the selected data model.
Provide the name of the template and save the report by clicking on the generate button.