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quarter()

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quarter()

quarter() is simple if you keep it on paper. Sara uses it for quarter on Sara's board in lab hour.

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

Skip quarter() and only reciting the name of quarter shows up in lab hour.

Use quarter() when quarter on Sara's board must stay clear. If a simpler SQL step works, use that instead.

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

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

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

Exam tip

Board: quarter on Sara's board. Dry-run quarter(). Name the trap: only reciting the name of quarter.

quarter() — sample query

-- quarter()
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;

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

Short notes

Defquarter() — Sara uses it for quarter on Sara's board in lab hour.
Rulequarter() → one quarter step Sara can write from memory.
Rememberquarter() + an index (lab hour).
Usequarter() in lab hour (quarter on Sara's board).
Trapquarter() — only reciting the name of quarter.
Exquarter() → quarter on Sara's board.

-- quarter() 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;

quarter()

quarter() — sample query

Short notes

Questions

quarter()

quarter() — sample query

Short notes

Questions