How do relational databases work?
In: Technology
Basically all the important “things” you identify get a table, which you can imagine like a glorified spreadsheet. A Person. A Job Position. A City. You can then have columns for each piece of information you care about for each “thing” you have. You could keep track of each person’s age for example. But something else interesting happens here. You can also keep track of their children (other Persons), their job position (a Job Position), and their city of residence (a City). These “things” exist as records in another table. So you give each record a unique identifier called a “key” so you can use it to refer to only that thing (i.e. you wouldn’t want to use someone’s name as a key since many people can share the same names) anywhere else in your database so that when you’re asking for something specific (e.g. I want to see every Person who worked this specific Position and lived in this specific City), it can give you a clean answer. If you simply let someone write down their city otherwise, you’d get problems like, maybe they wrote St Paul instead of Saint Paul, or something like that, and it gets much messier trying to find information you want.
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