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Versions

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Versions

Don’t start Versions with jargon. Start with Versions on Kabir's board. That is the whole point.

Keep Versions small. Kabir should finish Versions on Kabir's board in a few lines, not a 40-line dump.

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

Kabir ships Versions in lab hour. That is the use case worth saying.

Don’t do this with Versions — only reciting the name of Versions. Interviewers spot it in ten seconds.

Versions is not a lonely heading. Kabir ties it to Versions on Kabir's board.

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

Exam tip

For Versions: definition + lab hour + one failure.

Versions — sample query

-- Versions
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;

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

Short notes

DefVersions — Kabir uses it for Versions on Kabir's board in lab hour.
RuleVersions → one Versions step Kabir can write from memory.
RememberVersions + InnoDB (lab hour).
UseVersions in lab hour (Versions on Kabir's board).
TrapVersions — only reciting the name of Versions.
ExVersions → Versions on Kabir's board.

-- Versions 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;

Versions

Versions — sample query

Short notes

Questions

Versions

Versions — sample query

Short notes

Questions