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Math

Math functions — ABS, ROUND, FLOOR, CEIL, MOD, POW. SELECT ROUND(AVG(marks), 1) FROM students;

Use DECIMAL for money, then ROUND for display. RAND() is random — not for cryptography.

Trap — TRUNCATE(x,d) vs TRUNCATE TABLE. Different commands.

On the example next to this theory: Math: create two demo rows, then SELECT qty >= 2 ordered. Say which labels come back.

Exam tip

ROUND / ABS / MOD with one numeric SELECT.

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 functions take numbers, return numbers.
RuleROUND for display. DECIMAL for money.
TrapTRUNCATE function vs TRUNCATE TABLE.

-- 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