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Host

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Host

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

Host on the board — one Host step Arun can write from memory. Then say what a Host dry-run looks like after.

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

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

Host trap — skipping the failure case for Host. Arun loses marks for that every viva.

After Host, Arun should still remember skipping the failure case for Host.

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

Exam tip

For Host: definition + a viva board + one failure.

Host — sample query

-- Host
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;

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

Short notes

DefHost — Arun uses it for a Host dry-run in a viva board.
RuleHost → one Host step Arun can write from memory.
RememberHost + InnoDB (a viva board).
UseHost in a viva board (a Host dry-run).
TrapHost — skipping the failure case for Host.
ExHost → a Host dry-run.

-- Host 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;

Host

Host — sample query

Short notes

Questions

Host

Host — sample query

Short notes

Questions