Yeah, I work daily with a database with a very important non-ID field that is denormalized throughout most of the database. It’s not a common design pattern, but it is done from time to time.

It’s necessary to split it out into different tables if you have a one-to-many relationship. Let’s say you have a list of driver licenses the person has had over the years, for example. Then you’d need the second table. So something like this:

SSN_Table

ID | SSN | Other info

Driver_License_Table

ID | SSN_ID | Issue_Date | Expiry_Date | Other_Info

Then you could do something like pull up a person’s latest driver’s license, or list all the ones they had, or pull up the SSN associated with that license.

Theoretically, yeah, that’s one solution. The more reasonable thing to do would be to use the foreign key though. So, for example:

SSN_Table

ID | SSN | Other info

Other_Table

ID | SSN_ID | Other info

When you want to connect them to have both sets of info, it’d be the following:

SELECT * FROM SSN_Table JOIN Other_Table ON SSN_Table.ID = Other_Table.SSN_ID

EDIT: Oh, just to clear up any confusion, the SSN_ID in this simple example is not the SSN itself. To access that in this example query, it’d by SSN_Table.SSN

Here ya go

Short version: he might have frozen hiring air traffic controllers, he might not have. The ambiguity caused de facto hiring freezes in a profession that was already understaffed and vital to air safety.

There is a legitimate argument to be made with reasonable people on both sides as to exactly how old is old enough to confidently say that there’s not a power imbalance due to age alone. Whether that’s 18, 21, 24 or some other number is an open question.

30+? If they wanna date somebody more than double their age, that’s completely their business.