mysql - sql合并成格以选择案例

Question

我有 2 个表，想要从 2 个有条件的表中获取行总和 结果是这样的，例如 sh2 : 19 + 5 + 11 + 5 = 40 对于每个名称将它们全部计算在表中 我使用该代码

select name, sum(total) total from 
(select name, sum(coalesce(sk,ss)) total
 from table1
 group by name
 union all
 select name, sum(coalesce(sk,ss)) total
 from table2
 group by name
) t
group by name

但我想对该代码使用 select 和 case

Answer 1

select name,SUM(total)total from(
      select name,sum(case when sk>0 then sk else ss end )total from majale group by name
      union all
      select name,sum(case when sk>0 then sk else ss end )from ketab group by name
      union all
      select name,sum(case when sk>0 then sk else ss end )from savabegh group by name
      )t
      group by name