The lie made into the rule of the world

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Joined 4 months ago
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Cake day: October 22nd, 2024

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  • In the context of this tweet most important differences are:

    SQL is a language for querying databases.

    Most common used databases are relational databases. With relational databases you can setup, well, relations and constraints.

    Imagine you have 2 tables (2 excel sheets) one with people, and one with home ownership. You can set the following constraint: (1) each person shows up only once in the people table. And the following relation: (2) every home owner must refer to an existing person in people table.

    When modifying the table contents, the system checks if no constraints or relations are violated.

    Excel, just like a badly designed relational databse, would, for example, have no problem with duplicate people, or home ownership referring to non-existant people.