How does this pic show that Elon Musk doesnt know SQL?
Garlicsquash @ Garlicsquash @lemmings.world Posts 0Comments 4Joined 5 mo. ago
Garlicsquash @ Garlicsquash @lemmings.world
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Having never seen the database schema myself, my read is that the SSN is used as a primary key in one table, and many other tables likely use that as a foreign key. He probably doesn't understand that foreign keys are used as links and should not be de-duplicated, as that breaks the key relationship in a relational database. As others have mentioned, even in the main table there are probably reused or updated SSNs that would then be multiple rows that have timestamps and/or Boolean flags for current/expired.