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Sysdate()

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Sysdate()

Sysdate() is simple if you keep it on paper. Zara uses it for a Sysdate dry-run in lab hour.

For Sysdate(), InnoDB is in play. Don’t blame it until you have traced a Sysdate dry-run.

Without Sysdate(), lab hour gets messy and a Sysdate dry-run is hard to trust.

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

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

After Sysdate(), Zara should still remember skipping the failure case for Sysdate.

Viva for Sysdate(): what it is → one Sysdate step Zara can write from memory → the mistake (skipping the failure case for Sysdate).

Exam tip

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

Sysdate() — sample query

-- Sysdate()
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;

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

Short notes

DefSysdate() — Zara uses it for a Sysdate dry-run in lab hour.
RuleSysdate() → one Sysdate step Zara can write from memory.
RememberSysdate() + InnoDB (lab hour).
UseSysdate() in lab hour (a Sysdate dry-run).
TrapSysdate() — skipping the failure case for Sysdate.
ExSysdate() → a Sysdate dry-run.

-- Sysdate() 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;

Sysdate()

Sysdate() — sample query

Short notes

Questions

Sysdate()

Sysdate() — sample query

Short notes

Questions