1.先分组 group by-----然后在分组里面继续选择-----having
select product_type,count(*) from prodect group by product_type having count(*)=2
2.order by 排序1,排序2
3.insert into 表名 (列名1,2,3) values (值1,2,3)
复制表----insert into select from
update 表名
set ()
where
1.先分组 group by-----然后在分组里面继续选择-----having
select product_type,count(*) from prodect group by product_type having count(*)=2
2.order by 排序1,排序2
3.insert into 表名 (列名1,2,3) values (值1,2,3)
复制表----insert into select from
update 表名
set ()
where