>Edward,
>
>I think the problem is that you might run out of records to delete from the latter tables, maybe the process should start with the tables ordered by the number of records to delete to minimize this.
>
>Ex. (r records and d records to delete)
>
>T1: 500r 30d
>T2: 100r 10d
>T3: 111r 3d && You might already run out of duplicates to delete from this table

That's a good idea. It makes sense to start from the table with the minimum number of required deletions. As I mentioned before, exact result, i.e. absolutely correct proportion is not reachable, so one should try to get the best randomization.