SQL · Theory

POW()()

Theory

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POW()()

Don’t start POW()() (math) with jargon. Start with a POW math dry-run. That is the whole point.

Do POW()() (math) once by hand. one POW math step Dev can write from memory. Change one input. Say the new result out loud.

POW()() (math) exists so Dev can keep a POW math dry-run correct in lab hour.

POW()() (math) shows up in lab hour. Name a POW math dry-run, not “a real-world scenario”.

POW()() (math) miss — copy-pasting POW math without a dry-run. Fix it before you talk about advanced SQL.

POW()() (math) is not a lonely heading. Dev ties it to a POW math dry-run.

Close POW()() (math) with: “If I skip it, a POW math dry-run goes wrong like this: copy-pasting POW math without a dry-run.”

Exam tip

Board: a POW math dry-run. Dry-run POW()() (math). Name the trap: copy-pasting POW math without a dry-run.

POW()() — sample query

-- POW()()
CREATE TABLE demo (
  id INTEGER PRIMARY KEY,
  label TEXT NOT NULL,
  qty INTEGER DEFAULT 0
);
INSERT INTO demo (id, label, qty) VALUES
  (1, 'alpha', 2),
  (2, 'beta', 5);
SELECT label, qty FROM demo WHERE qty >= 2 ORDER BY qty DESC;

POW()(): create two demo rows, then SELECT qty >= 2 ordered. Say which labels come back.

Short notes

DefPOW()() (math) — Dev uses it for a POW math dry-run in lab hour.
RulePOW()() (math) → one POW math step Dev can write from memory.
RememberPOW()() (math) + an index (lab hour).
UsePOW()() (math) in lab hour (a POW math dry-run).
TrapPOW()() (math) — copy-pasting POW math without a dry-run.
ExPOW()() (math) → a POW math dry-run.

-- POW()() CREATE TABLE demo ( id INTEGER PRIMARY KEY, label TEXT NOT NULL, qty INTEGER DEFAULT 0 ); INSERT INTO demo (id, label, qty) VALUES (1, 'alpha', 2), (2, 'beta', 5); SELECT label, qty FROM demo WHERE qty >= 2 ORDER BY qty DESC;

POW()()

POW()() — sample query

Short notes

Questions

POW()()

POW()() — sample query

Short notes

Questions