Submitted by whitemice on Sun, 09/29/2013 - 09:14
Idempotent values are hard to come by [in relational database terms these are what we call "primary keys"]; they uniquely identify some record, or value, or object. At least you are certain they do... until they don't. The great big world has a habit of not respecting the idem-potency of what you declare to be idempotent; something out there just recycles it anyway. This is no less true in IT systems like ERP applications than it is anywhere else.