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DAY()

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DAY()

DAY() is simple if you keep it on paper. Sara uses it for a DAY dry-run in a campus project.

Keep DAY() small. Sara should finish a DAY dry-run in a few lines, not a 40-line dump.

DAY() exists so Sara can keep a DAY dry-run correct in a campus project.

DAY() shows up in a campus project. Name a DAY dry-run, not “a real-world scenario”.

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

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

Viva for DAY() — what it is → one DAY step Sara can write from memory → the mistake (skipping the failure case for DAY).

Exam tip

Board: a DAY dry-run. Dry-run DAY(). Name the trap: skipping the failure case for DAY.

DAY() — sample query

-- 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;

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

Short notes

DefDAY() — Sara uses it for a DAY dry-run in a campus project.
RuleDAY() → one DAY step Sara can write from memory.
RememberDAY() + an index (a campus project).
UseDAY() in a campus project (a DAY dry-run).
TrapDAY() — skipping the failure case for DAY.
ExDAY() → a DAY dry-run.

-- 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;

DAY()

DAY() — sample query

Short notes

Questions

DAY()

DAY() — sample query

Short notes

Questions