mysql - 如何按组菜单对数据进行排序？

Question

如何按groupmenu对数据进行排序？

mysql

SELECT pc.pc_id, pc.pc_icon, pc.pc_parent, pcd.pcd_name, pcd.pcd_id 
FROM product_category pc 
LEFT JOIN product_category_detail pcd ON pcd.pc_id=pc.pc_id 
ORDER BY pc.pc_group, pc.pc_sort, pc.pc_id

我想显示内容菜单

例如

• 测试6
• -subtest6
• --subtest6-2
• ---subtest6-2-1
• 测试7

如何查询？

Answer 1

如果你想要无限的子菜单，使用PHP循环可能会更容易。

生成 2 级菜单仍然很容易，例如

SELECT a.id,
FROM 
SELECT pc.pc_id, pc.pc_icon, pc.pc_parent, pcd.pcd_id,
concat(if (pc.pc_parent = 0, '', '- '), pcd.pcd_name) AS pcd_name
FROM product_category AS pc
LEFT JOIN product_category_detail AS pcd ON pcd.pc_id = pc.pc_id

按 pc.pc_group、pc.pc_sort、pc.pc_id 排序

或者您可以重新设计类别表以拥有简单且无限的子菜单树:

pc_id
11
1122   -- kid of 11
112233 -- kid of 1122
55
66
6677   -- kid of 66