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CREATE TABLE tablename (`day` INTEGER, `person` VARCHAR(4), `amount` INTEGER);
INSERT INTO tablename (`day`, `person`, `amount`) VALUES
('1', 'John', '4'),
('1', 'Sam', '6'),
('2', 'John', '3'),
('3', 'John', '3'),
('3', 'Sam', '5'),
('4', 'John', '3');
Records: 6 Duplicates: 0 Warnings: 0
SELECT person,
100 * AVG(amount > 3) percent
FROM tablename
GROUP BY person;
| person | percent |
|---|---|
| John | 25.0000 |
| Sam | 100.0000 |
SELECT person,
100 * AVG(amount > 5) percent
FROM tablename
GROUP BY person;
| person | percent |
|---|---|
| John | 0.0000 |
| Sam | 50.0000 |