Best option would be to run a cron job which just reads out the data from source and put within the target as per the requirement.It would be a one time job... but less painful in long run.
Cron jobs are repeating / scheduled jobs - if this is a one time thing just create a run the script - or - if you want to schedule it to run once - use 'at' instead of 'cron'. This of course assumes that the original question was being asked with regard to a UNIX implementation. For Windows it's generally the Windows Scheduler or WinAT that is used - but again, if it is a one-time thing just run the script and forget about scheduling.