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ENUM

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ENUM

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

For ENUM, the query planner is in play. Don’t blame it until you have traced ENUM on Kabir's board.

Without ENUM, lab hour gets messy and ENUM on Kabir's board is hard to trust.

Use ENUM when ENUM on Kabir's board must stay clear. If a simpler SQL step works, use that instead.

If ENUM on Kabir's board breaks under ENUM, check skipping the failure case for ENUM first.

Place ENUM next to nearby SQL work — one ENUM step Kabir can write from memory is the link.

Close ENUM with — “If I skip it, ENUM on Kabir's board goes wrong like this: skipping the failure case for ENUM.”

Exam tip

For ENUM: definition + lab hour + one failure.

ENUM — sample query

-- ENUM
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;

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

Short notes

DefENUM — Kabir uses it for ENUM on Kabir's board in lab hour.
RuleENUM → one ENUM step Kabir can write from memory.
RememberENUM + the query planner (lab hour).
UseENUM in lab hour (ENUM on Kabir's board).
TrapENUM — skipping the failure case for ENUM.
ExENUM → ENUM on Kabir's board.

-- ENUM 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;

ENUM

ENUM — sample query

Short notes

Questions

ENUM

ENUM — sample query

Short notes

Questions