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Views

Don’t start Views with jargon. Start with a fail-list view. That is the whole point.

For Views, InnoDB is in play. Don’t blame it until you have traced a fail-list view.

Views exists so Riya can keep a fail-list view correct in teachers’ report.

Riya ships Views in teachers’ report. That is the use case worth saying.

Views trap — trying to UPDATE a non-updatable view. Riya loses marks for that every viva.

Place Views next to nearby SQL work — CREATE VIEW fail_list AS … is the link.

Close Views with — “If I skip it, a fail-list view goes wrong like this: trying to UPDATE a non-updatable view.”

Exam tip

Say Views in one breath, then CREATE VIEW fail_list AS …, then trying to UPDATE a non-updatable view.

Views — sample query

-- Views
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;

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

Short notes

DefViews — Riya uses it for a fail-list view in teachers’ report.
RuleViews → CREATE VIEW fail_list AS ….
RememberViews + InnoDB (teachers’ report).
UseViews in teachers’ report (a fail-list view).
TrapViews — trying to UPDATE a non-updatable view.
ExViews → a fail-list view.

-- Views 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;

Views

Views — sample query

Short notes

Questions

Views

Views — sample query

Short notes

Questions