The first thing what you need know: VERY Important! Using pdm_load can be destructive so always back up your database before you perform a pdm_load, and use pdm_userload unless instructed to use pdm_load.
Important! Make a backup copy of the database before running pdm_load with this option. After old database records are removed, you must restore the CA SDM database with this backup copy if you want to recover any deleted records, use pdm_extract for this procedure.