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Math

Math is a SQL idea you prove with Farhan walking through Math, not with a slogan.

Keep Math small. Farhan should finish Farhan walking through Math in a few lines, not a 40-line dump.

Math exists so Farhan can keep Farhan walking through Math correct in lab hour.

Use Math when Farhan walking through Math must stay clear. If a simpler SQL step works, use that instead.

Math trap — copy-pasting Math without a dry-run. Farhan loses marks for that every viva.

Place Math next to nearby SQL work — one Math step Farhan can write from memory is the link.

Close Math with — “If I skip it, Farhan walking through Math goes wrong like this: copy-pasting Math without a dry-run.”

Exam tip

Board: Farhan walking through Math. Dry-run Math. Name the trap: copy-pasting Math without a dry-run.

Math — sample query

-- Math
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;

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

Short notes

DefMath — Farhan uses it for Farhan walking through Math in lab hour.
RuleMath → one Math step Farhan can write from memory.
RememberMath + InnoDB (lab hour).
UseMath in lab hour (Farhan walking through Math).
TrapMath — copy-pasting Math without a dry-run.
ExMath → Farhan walking through Math.

-- Math 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;

Math

Math — sample query

Short notes

Questions

Math

Math — sample query

Short notes

Questions