John:
There's a couple of issues with using SSNs.
Technically, they are not unique. Several people have received duplicate numbers, so they're not ideal primary keys.
Second, they are considered "secret" Personally Identifiable Information (often PII) and disclosure of such information can be a considered a data breach, leaving you liable to state, local, federal and international laws (like GDPR) requiring you to provide disclosure, notification and possible liability.
They're also pretty easy to guess. The first two designates the state of birth, easy to find, the last four and printed on FAR too many documents, and the three in the middle were issued chronologically, so knowing a birthdate narrows the guessing down by far.
When I was in bootcamp in 1979, they gave us all stencils and required us to have our name and service number, also our SSN on the hundreds of pieces of uniform and gear we were issued. I've still got a few in my basement and attic. Some secret!
On Mon, Feb 25, 2019 at 11:13 AM John Weller john@johnweller.co.uk wrote:
Purely out of curiosity and not being familiar with your SSNs (Social Security Numbers I assume) can I ask what is the problem with using them as a PK?
John Weller 01380 723235 07976 393631
I must confess.... I did this once and used SSN's as a primary key. It is my shame....
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