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Account Unlock

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Account Unlock

If you can teach Account Unlock using average per subject, you know it. If you only know the heading, you don’t.

Keep Account Unlock small. Ananya should finish average per subject in a few lines, not a 40-line dump.

Without Account Unlock, a report gets messy and average per subject is hard to trust.

Account Unlock shows up in a report. Name average per subject, not “a real-world scenario”.

Account Unlock miss — SELECT extra column not in GROUP BY. Fix it before you talk about advanced SQL.

After Account Unlock, Ananya should still remember SELECT extra column not in GROUP BY.

Viva for Account Unlock — what it is → GROUP BY subject → the mistake (SELECT extra column not in GROUP BY).

Exam tip

Board: average per subject. Dry-run Account Unlock. Name the trap: SELECT extra column not in GROUP BY.

Account Unlock — sample query

-- Account Unlock
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;

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

Short notes

DefAccount Unlock — Ananya uses it for average per subject in a report.
RuleAccount Unlock → GROUP BY subject.
RememberAccount Unlock + InnoDB (a report).
UseAccount Unlock in a report (average per subject).
TrapAccount Unlock — SELECT extra column not in GROUP BY.
ExAccount Unlock → average per subject.

-- Account Unlock 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;

Account Unlock

Account Unlock — sample query

Short notes

Questions

Account Unlock

Account Unlock — sample query

Short notes

Questions