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Storage Engines

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Storage Engines

Meera only reaches for Storage Engines when a Storage Engines dry-run has to stay correct in lab hour.

For Storage Engines, the query planner is in play. Don’t blame it until you have traced a Storage Engines dry-run.

Without Storage Engines, lab hour gets messy and a Storage Engines dry-run is hard to trust.

Storage Engines shows up in lab hour. Name a Storage Engines dry-run, not “a real-world scenario”.

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

After Storage Engines, Meera should still remember only reciting the name of Storage Engines.

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

Exam tip

For Storage Engines: definition + lab hour + one failure.

Storage Engines — sample query

-- Storage Engines
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;

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

Short notes

DefStorage Engines — Meera uses it for a Storage Engines dry-run in lab hour.
RuleStorage Engines → one Storage Engines step Meera can write from memory.
RememberStorage Engines + the query planner (lab hour).
UseStorage Engines in lab hour (a Storage Engines dry-run).
TrapStorage Engines — only reciting the name of Storage Engines.
ExStorage Engines → a Storage Engines dry-run.

-- Storage Engines 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;

Storage Engines

Storage Engines — sample query

Short notes

Questions

Storage Engines

Storage Engines — sample query

Short notes

Questions