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weekday()

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weekday()

If you can teach weekday() using a weekday dry-run, you know it. If you only know the heading, you don’t.

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

Without weekday(), a viva board gets messy and a weekday dry-run is hard to trust.

Use weekday() when a weekday dry-run must stay clear. If a simpler SQL step works, use that instead.

weekday() miss — skipping the failure case for weekday. Fix it before you talk about advanced SQL.

Place weekday() next to nearby SQL work — one weekday step Zara can write from memory is the link.

Viva for weekday(): what it is → one weekday step Zara can write from memory → the mistake (skipping the failure case for weekday).

Exam tip

Say weekday() in one breath, then one weekday step Zara can write from memory, then skipping the failure case for weekday.

weekday() — sample query

-- weekday()
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;

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

Short notes

Defweekday() — Zara uses it for a weekday dry-run in a viva board.
Ruleweekday() → one weekday step Zara can write from memory.
Rememberweekday() + the query planner (a viva board).
Useweekday() in a viva board (a weekday dry-run).
Trapweekday() — skipping the failure case for weekday.
Exweekday() → a weekday dry-run.

-- weekday() 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;

weekday()

weekday() — sample query

Short notes

Questions

weekday()

weekday() — sample query

Short notes

Questions