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The Structured Query Language

Love Notes​

It’s lovely and declarative (what not how), simple and powerful, and will stand the test of time. Quoting this lovely article (cached):

SQL is the only programming language a working developer can learn once and use for 30 years without rewriting their mental model. That claim sounds like nostalgia, but it rests on something more durable.

Open any SQL textbook from 1995. Find the example query:

SELECT department, COUNT(*) AS headcount
FROM employees
WHERE hire_date > '1994-01-01'
GROUP BY department
HAVING COUNT(*) > 5
ORDER BY headcount DESC;

Paste it into PostgreSQL 18 in 2026. It runs. Same syntax, same result, same mental model. Thirty-one years, zero changes.

In my own experience, it is one of the few languages where I have spent way more time thinking than typing (and have been awestruck by people whose incantations are way more elegant and faster than mine!)

Logical Evaluation Order​

You certainly write SELECT ... FROM ... WHERE ..., but it’s conceptually evaluated in a different order (remember: Projection happens after Selection).