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Minus

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Minus

Minus is a SQL idea you prove with Minus on Dev's board, not with a slogan.

Minus order — meaning → one Minus step Dev can write from memory → one limit. Dumping ten features helps nobody.

Without Minus, a viva board gets messy and Minus on Dev's board is hard to trust.

Use Minus when Minus on Dev's board must stay clear. If a simpler SQL step works, use that instead.

If Minus on Dev's board breaks under Minus, check only reciting the name of Minus first.

After Minus, Dev should still remember only reciting the name of Minus.

One breath for Minus, then Minus on Dev's board, then only reciting the name of Minus. Sit down.

Exam tip

Board: Minus on Dev's board. Dry-run Minus. Name the trap: only reciting the name of Minus.

Minus — sample query

-- Minus
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;

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

Short notes

DefMinus — Dev uses it for Minus on Dev's board in a viva board.
RuleMinus → one Minus step Dev can write from memory.
RememberMinus + an index (a viva board).
UseMinus in a viva board (Minus on Dev's board).
TrapMinus — only reciting the name of Minus.
ExMinus → Minus on Dev's board.

-- Minus 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;

Minus

Minus — sample query

Short notes

Questions

Minus

Minus — sample query

Short notes

Questions