At the moment, ADT/ADI & Temp directory all have to be on the same drive. Some users prefer not to rebuild ADI on the data-disk - some would really like to put the table/idexes on different drives, perhaps the ADI in ramdisk, if they could, then they would be able to keep the data within ramdisk size limits, reduce wear-levelling on SSD and possibly get ADT tables on the rotary-disks. Users would like to be able to specify the drive where to put the ADI using the existing user-interface for relocating the index - and specify a different drive for the 'Temp' directory used by the data dictionary.