jion 操作语法异常

jion 操作语法错误
"select ys1.单位,sum(ys1.预算) as 预算 from ys1 left join (select sum(ch.数量) as 数量 from ch group by ch.用料单位,ys1.单位) on ys1.单位 = ch.用料单位

[解决办法]
select ys1.单位,sum(ys1.预算) as 预算 from ys1 left join (select sum(ch.数量) as 数量 from ch group by ch.用料单位,ys1.单位) as ch on ys1.单位 = ch.用料单位
[解决办法]

SQL code

select ys1.*,ch.数量 from (select 单位,sum(预算) as 预算 from ys1 group by 单位) as ys1left join (select 用料单位,sum(数量) as 数量 from ch group by 用料单位) as chon ys1.单位 = ch.用料单位