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now()

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now()

If you can teach now() using now on Asha's board, you know it. If you only know the heading, you don’t.

For now(), InnoDB is in play. Don’t blame it until you have traced now on Asha's board.

Without now(), a first job task gets messy and now on Asha's board is hard to trust.

Use now() when now on Asha's board must stay clear. If a simpler SQL step works, use that instead.

now() trap — skipping the failure case for now. Asha loses marks for that every viva.

now() is not a lonely heading. Asha ties it to now on Asha's board.

One breath for now(), then now on Asha's board, then skipping the failure case for now. Sit down.

Exam tip

Board: now on Asha's board. Dry-run now(). Name the trap: skipping the failure case for now.

now() — sample query

-- now()
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;

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

Short notes

Defnow() — Asha uses it for now on Asha's board in a first job task.
Rulenow() → one now step Asha can write from memory.
Remembernow() + InnoDB (a first job task).
Usenow() in a first job task (now on Asha's board).
Trapnow() — skipping the failure case for now.
Exnow() → now on Asha's board.

-- now() 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;

now()

now() — sample query

Short notes

Questions

now()

now() — sample query

Short notes

Questions