2 answers
Not having a full copy sandbox in our org limits me from being able to test this in a full scale for that amount of records.The way I see it is I would hit DML limits of 10,000 updates via Apex and (for obvious reasons) leverage config vs code. Scheduled Apex allows for more but not on that scale. I don't care so much about the time it may take (within reason of course so let's say 6-8 hours processing time is ok) as long as I don't hit a governor limits and workflow/field updates are suspended for a period of time as a result. Any daily limits known for this?