1、商品表 goods
2、门店表 store
| id |
title |
| 1 |
成都店 |
| 2 |
华阳店 |
| 3 |
高新店 |
3、关联表 goods_store
| goods_id |
store_id |
| 1 |
1 |
| 1 |
2 |
| 2 |
1 |
| 2 |
2 |
| 2 |
3 |
5、普通连表查询结果
SELECT
g.*,
s.title as store_title
FROM goods as g
JOIN goods_store as gs ON g.id=gs.goods_id
JOIN store as s ON gs.store_id=s.id
| id |
title |
store_title |
| 1 |
奶茶 |
成都店 |
| 1 |
奶茶 |
华阳店 |
| 2 |
咖啡 |
成都店 |
| 2 |
咖啡 |
华阳店 |
| 2 |
咖啡 |
高新店 |
6、使用 GROUP_CONCAT 后
SELECT
g.*,
GROUP_CONCAT(s.title) as store_title
FROM goods as g
JOIN goods_store as gs ON g.id=gs.goods_id
JOIN store as s ON gs.store_id=s.id
GROUP BY g.id
| id |
title |
store_title |
| 1 |
奶茶 |
成都店,华阳店 |
| 2 |
咖啡 |
成都店,华阳店,高新店 |