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timestamp()

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timestamp()

timestamp() is simple if you keep it on paper. Ananya uses it for a timestamp dry-run in a viva board.

Keep timestamp() small. Ananya should finish a timestamp dry-run in a few lines, not a 40-line dump.

Without timestamp(), a viva board gets messy and a timestamp dry-run is hard to trust.

timestamp() shows up in a viva board. Name a timestamp dry-run, not “a real-world scenario”.

Don’t do this with timestamp() — skipping the failure case for timestamp. Interviewers spot it in ten seconds.

After timestamp(), Ananya should still remember skipping the failure case for timestamp.

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

Exam tip

For timestamp(): definition + a viva board + one failure.

timestamp() — sample query

-- timestamp()
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;

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

Short notes

Deftimestamp() — Ananya uses it for a timestamp dry-run in a viva board.
Ruletimestamp() → one timestamp step Ananya can write from memory.
Remembertimestamp() + the query planner (a viva board).
Usetimestamp() in a viva board (a timestamp dry-run).
Traptimestamp() — skipping the failure case for timestamp.
Extimestamp() → a timestamp dry-run.

-- timestamp() 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;

timestamp()

timestamp() — sample query

Short notes

Questions

timestamp()

timestamp() — sample query

Short notes

Questions