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DAYNAME()

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DAYNAME()

If you can teach DAYNAME() using DAYNAME on Zara's board, you know it. If you only know the heading, you don’t.

For DAYNAME(), an index is in play. Don’t blame it until you have traced DAYNAME on Zara's board.

DAYNAME() exists so Zara can keep DAYNAME on Zara's board correct in lab hour.

Zara ships DAYNAME() in lab hour. That is the use case worth saying.

Don’t do this with DAYNAME() — only reciting the name of DAYNAME. Interviewers spot it in ten seconds.

After DAYNAME(), Zara should still remember only reciting the name of DAYNAME.

One breath for DAYNAME(), then DAYNAME on Zara's board, then only reciting the name of DAYNAME. Sit down.

Exam tip

For DAYNAME(): definition + lab hour + one failure.

DAYNAME() — sample query

-- DAYNAME()
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;

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

Short notes

DefDAYNAME() — Zara uses it for DAYNAME on Zara's board in lab hour.
RuleDAYNAME() → one DAYNAME step Zara can write from memory.
RememberDAYNAME() + an index (lab hour).
UseDAYNAME() in lab hour (DAYNAME on Zara's board).
TrapDAYNAME() — only reciting the name of DAYNAME.
ExDAYNAME() → DAYNAME on Zara's board.

-- DAYNAME() 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;

DAYNAME()

DAYNAME() — sample query

Short notes

Questions

DAYNAME()

DAYNAME() — sample query

Short notes

Questions