Comment on How does this pic show that Elon Musk doesnt know SQL?
DahGangalang@infosec.pub 1 week agoHmmm, well I can’t speak to how the actual databases are put together, so maybe they would have that as two separate unique primary keys with a duplicated SSN.
But it really seems like bad design if they out it together that way…
JoeyJoeJoeJr@lemmy.ml 1 week ago
Worth noting is that “good” database design evolved over time (en.wikipedia.org/wiki/Database_normalization). If anything was setup pre-1970s, they wouldn’t have even had the conception of the normal forms used to cut down on data duplication. And even after they were defined, it would have been quite a while before the concepts trickled down from acedmemia to the engineers actually setting up the databases in production.
On top of that, name to SSN is a many-to-many relationship - a single person can legally change their name, and may have to apply for a new SSN (e.g. in the case of identity theft). So even in a well normalized database, when you query the data in a “useful” form (e.g. results include name and SSN), it’s probably going to appear as if there are multiple people using the same SSN, as well as multiple SSNs assigned to the same person.