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timediff()

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timediff()

Ananya only reaches for timediff() when Ananya walking through timediff has to stay correct in a small live site.

For timediff(), an index is in play. Don’t blame it until you have traced Ananya walking through timediff.

Without timediff(), a small live site gets messy and Ananya walking through timediff is hard to trust.

timediff() shows up in a small live site. Name Ananya walking through timediff, not “a real-world scenario”.

If Ananya walking through timediff breaks under timediff(), check only reciting the name of timediff first.

After timediff(), Ananya should still remember only reciting the name of timediff.

Viva for timediff(): what it is → one timediff step Ananya can write from memory → the mistake (only reciting the name of timediff).

Exam tip

Say timediff() in one breath, then one timediff step Ananya can write from memory, then only reciting the name of timediff.

timediff() — sample query

-- timediff()
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;

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

Short notes

Deftimediff() — Ananya uses it for Ananya walking through timediff in a small live site.
Ruletimediff() → one timediff step Ananya can write from memory.
Remembertimediff() + an index (a small live site).
Usetimediff() in a small live site (Ananya walking through timediff).
Traptimediff() — only reciting the name of timediff.
Extimediff() → Ananya walking through timediff.

-- timediff() 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;

timediff()

timediff() — sample query

Short notes

Questions

timediff()

timediff() — sample query

Short notes

Questions