Series · 5 parts · 14 min

Data and AI

Every kind of database was built to do something the one before it couldn't. This series takes them in the order they arrived: the brief history first, then SQL and what relational means, then NoSQL, vector and graph databases, and finally how an AI that seems to remember you is using several of them at once.

Watch them in order. Each stands on its own, but the questions build.

Start the series →
  1. A frame from the video: a timeline with five marks, Count, Find, Ask anything, Spread out and Meaning, each with a small drawing above it, and the chips Vector and Graph beneath. 2:18
    Video Part 1

    Why databases were created

    A database is where your records are kept so a computer can find them. There isn't just one kind. Five big steps, each built to do what the one before couldn't, in a little over two minutes.

  2. A frame from the video: a Customers table and an Orders table side by side, a line joining an order to its customer, and the word Relational beneath. 2:55
    Video Part 2

    SQL explained

    Why relational databases still run the world. What relational means, why a spreadsheet stops working, and what a database does instead: each fact stored once, rules that keep it honest, and a question you ask with SQL.

  3. A frame from the video: a key card labelled Customer 4172 turned into the number 8, a line to machine 8 in a grid of twelve, and dashed lines fanning out to every machine for a request without a key. 2:36
    Video Part 3

    NoSQL explained

    Built for records that don't all share one shape, and for more people than one machine can serve. Documents instead of rows, thousands of machines instead of one, found by their key, and the choice between agreeing first and answering now.

  4. A frame from the video: a search box reading my card was declined abroad beside a map of faint dots, with the question as an orange dot and the three nearest pieces lit in teal. 2:29
    Video Part 4

    Vector databases explained

    How a database finds what you mean rather than the words you typed, and how that lets an AI answer from your documents. Meaning as numbers, the nearest pieces found fast, and why the answer is only as good as what was found.

  5. A frame from the video: a query pattern above a field of faint linked dots, with the chain from a new customer to an account closed for fraud traced in orange. 3:25
    Video Part 5

    Graph databases explained

    When the links are the data. How a graph database stores each link beside the things it joins, why following a chain is a step rather than a search, and where that earns its place, from fraud rings to knowledge graphs and the AI systems that use them.

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