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last_day()

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Theory

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last_day()

last_day() is simple if you keep it on paper. Sara uses it for last_day on Sara's board in a viva board.

Keep last_day() small. Sara should finish last_day on Sara's board in a few lines, not a 40-line dump.

Skip last_day() and only reciting the name of last_day shows up in a viva board.

last_day() shows up in a viva board. Name last_day on Sara's board, not “a real-world scenario”.

If last_day on Sara's board breaks under last_day(), check only reciting the name of last_day first.

last_day() is not a lonely heading. Sara ties it to last_day on Sara's board.

Close last_day() with: “If I skip it, last_day on Sara's board goes wrong like this: only reciting the name of last_day.”

Exam tip

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

last_day() — sample query

-- last_day()
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;

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

Short notes

Deflast_day() — Sara uses it for last_day on Sara's board in a viva board.
Rulelast_day() → one last_day step Sara can write from memory.
Rememberlast_day() + an index (a viva board).
Uselast_day() in a viva board (last_day on Sara's board).
Traplast_day() — only reciting the name of last_day.
Exlast_day() → last_day on Sara's board.

-- last_day() 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;

last_day()

last_day() — sample query

Short notes

Questions

last_day()

last_day() — sample query

Short notes

Questions