问题描述
||
我在使此SQL运行时遇到困难。基本上,我想将列“ 1”设置为“ 0”,并将其设置为由同一表上的子查询选择的“ 2”。这是我的
SELECT
查询,显示了我需要的数据...
SELECT p.id,p.sort_order,p.parent_id,(
SELECT `sort_order` AS parent_sort_order
FROM `product`
WHERE id = p.parent_id
)
FROM `product` p
WHERE p.dealer_id !=0
AND p.vendor_id >100
谢谢!
解决方法
您选择的加入版本:
SELECT p.id,p.sort_order,p.parent_id,b.sort_order as parent_sort_order
FROM `product` p join `product` b
on p.id = b.parent_id
WHERE p.dealer_id !=0
AND p.vendor_id >100
更新选项1:
update product a,product b set a.sort_order = b.parent_sort_order
where a.id = b.parent_id
and a.dealer_id !=0
and a.vendor_id > 100
更新选项2:
update product a left join product b on a.id = b.parent_id
set a.sort_order = b.parent_sort_order
where a.dealer_id !=0
and a.vendor_id > 100