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Don’t start URL with jargon. Start with a URL dry-run. That is the whole point.

URL on the board — one URL step Dev can write from memory. Then say what a URL dry-run looks like after.

Skip URL and only reciting the name of URL shows up in lab hour.

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

If a URL dry-run breaks under URL, check only reciting the name of URL first.

After URL, Dev should still remember only reciting the name of URL.

Close URL with — “If I skip it, a URL dry-run goes wrong like this: only reciting the name of URL.”

Exam tip

For URL: definition + lab hour + one failure.

URL — sample query

-- URL
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;

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

Short notes

DefURL — Dev uses it for a URL dry-run in lab hour.
RuleURL → one URL step Dev can write from memory.
RememberURL + an index (lab hour).
UseURL in lab hour (a URL dry-run).
TrapURL — only reciting the name of URL.
ExURL → a URL dry-run.

-- URL 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;

URL

URL — sample query

Short notes

Questions

URL

URL — sample query

Short notes

Questions