DB view associated with CDT but don't have primary Key. We used DB View in a!ExportDataStoreEntityToExcel to extract data into Excel File and getting timeout error.

DB view associated with CDT but don't have primary Key. We used DB View in a!ExportDataStoreEntityToExcel to extract data(20k Records) into Excel File and getting an timeout Error. Is there any way to apply Composite Key for few columns on CDT to extract data to Excel without errors ? In Appian Best Practices mentioned that there is a way to apply composite key but no example. If anyone knows the solution please replay here. Thank you.