Ron Johnson <ron.l.johnson@xxxxxxx> writes: > On 03/01/2018 02:08 PM, marcelo wrote: >> >> >> On 01/03/2018 16:42 , Ron Johnson wrote: >>> On 03/01/2018 01:11 PM, marcelo wrote: >>>> >>>> On 01/03/2018 16:00 , Ron Johnson wrote: >>> [snip] >>>>> If your only unique index is a synthetic key, then you can insert the >>>>> same "business data" multiple times with different synthetic keys. >>>>> >>>>> >>>>> -- >>>>> Angular momentum makes the world go 'round. >>>> IMHO, business logic can and must preclude "garbage insertion". Except >>>> you are inserting data directly to database using SQL, any n-tier >>>> architecture will be checking data validity. >>> >>> Any n-tier architecture that's bug-free. >>> >> Do you know about unit testing? > > Way Back When Dinosaurs Still Roamed The Earth and I first learned the > trade, the focus was on proper design instead of throwing crud against the > wall and hoping tests caught any bugs. Because, of course, unit tests are > only as good as you imagination in devising tests. +1. And a good test of your underlying data model is whether you can identify a natural primary key. If you can't, chances are your model is immature/flawed and needs more analysis. -- Tim Cross
