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Repair Table

Theory

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Repair Table

REPAIR TABLE is mainly for MyISAM tables that got corrupted. InnoDB almost never wants REPAIR TABLE — you use dump/restore or innodb recovery settings instead.

If a teacher’s old lab uses MyISAM and SELECT crashes, they may show REPAIR TABLE t; Don’t make it your default InnoDB answer.

Trap — REPAIR TABLE on InnoDB and thinking it ‘optimises’ like OPTIMIZE TABLE.

On the example next to this theory: Repair Table: create two demo rows, then SELECT qty >= 2 ordered. Say which labels come back.

Exam tip

MyISAM: REPAIR TABLE. InnoDB: don’t; restore from backup.

Repair Table — sample query

-- Repair Table
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;

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

Short notes

DefREPAIR TABLE is a MyISAM recovery command.
RuleInnoDB → dump/restore, not REPAIR.
TrapUsing REPAIR on InnoDB as a habit.

-- Repair Table 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;

Repair Table

Repair Table — sample query

Short notes

Questions

Repair Table

Repair Table — sample query

Short notes

Questions