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CREATE TABLE Parent
(id INT,title VARCHAR(50));
INSERT INTO Parent VALUES
(1,'A'),
(2,'B'),
(3,'C');
CREATE TABLE Childs
(id INT, p_id INT, number INT);
INSERT INTO Childs VALUES
(1,1,1),(2,1,2),(3,1,3),
(4,2,4),(5,2,5),(6,2,6),
(7,3,2),(8,3,7),(9,3,8),(10,3,9);
Records: 3 Duplicates: 0 Warnings: 0
Records: 10 Duplicates: 0 Warnings: 0
SELECT p.id, p.title, GROUP_CONCAT(number ORDER BY number) val
FROM Parent p JOIN Childs c ON p.id=c.p_id
GROUP BY p.id, p.title
HAVING SUBSTRING_INDEX(val,',',1) > 3;
| id | title | val |
|---|---|---|
| 2 | B | 4,5,6 |
/*without HAVING clause*/
SELECT p.id, p.title, GROUP_CONCAT(number ORDER BY number) val
FROM Parent p JOIN Childs c ON p.id=c.p_id
GROUP BY p.id, p.title;
| id | title | val |
|---|---|---|
| 1 | A | 1,2,3 |
| 2 | B | 4,5,6 |
| 3 | C | 2,7,8,9 |