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Free Course

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Free Course

Sara only reaches for Free Course when a Free Course dry-run has to stay correct in a first job task.

Keep Free Course small. Sara should finish a Free Course dry-run in a few lines, not a 40-line dump.

Free Course exists so Sara can keep a Free Course dry-run correct in a first job task.

Use Free Course when a Free Course dry-run must stay clear. If a simpler SQL step works, use that instead.

Don’t do this with Free Course — skipping the failure case for Free Course. Interviewers spot it in ten seconds.

Place Free Course next to nearby SQL work — one Free Course step Sara can write from memory is the link.

Close Free Course with: “If I skip it, a Free Course dry-run goes wrong like this: skipping the failure case for Free Course.”

Exam tip

For Free Course: definition + a first job task + one failure.

Free Course — sample query

-- Free Course
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;

Free Course: create two demo rows, then SELECT qty >= 2 ordered. Say which labels come back.

Short notes

DefFree Course — Sara uses it for a Free Course dry-run in a first job task.
RuleFree Course → one Free Course step Sara can write from memory.
RememberFree Course + InnoDB (a first job task).
UseFree Course in a first job task (a Free Course dry-run).
TrapFree Course — skipping the failure case for Free Course.
ExFree Course → a Free Course dry-run.

-- Free Course 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;

Free Course

Free Course — sample query

Short notes

Questions

Free Course

Free Course — sample query

Short notes

Questions