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Interval

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Interval

Interval is a SQL idea you prove with a Interval dry-run, not with a slogan.

Keep Interval small. Neha should finish a Interval dry-run in a few lines, not a 40-line dump.

Skip Interval and only reciting the name of Interval shows up in a first job task.

Interval shows up in a first job task. Name a Interval dry-run, not “a real-world scenario”.

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

After Interval, Neha should still remember only reciting the name of Interval.

Close Interval with — “If I skip it, a Interval dry-run goes wrong like this: only reciting the name of Interval.”

Exam tip

For Interval: definition + a first job task + one failure.

Interval — sample query

-- Interval
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;

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

Short notes

DefInterval — Neha uses it for a Interval dry-run in a first job task.
RuleInterval → one Interval step Neha can write from memory.
RememberInterval + InnoDB (a first job task).
UseInterval in a first job task (a Interval dry-run).
TrapInterval — only reciting the name of Interval.
ExInterval → a Interval dry-run.

-- Interval 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;

Interval

Interval — sample query

Short notes

Questions

Interval

Interval — sample query

Short notes

Questions