SQL 查询合并

SQL 查询合并

select t.供应商,sum(t.收入),sum(t.支出)
(select 表1.a as '供应商',表2.b as '收入',0 as '支出' from A,B where 表2.c=1
union
select 表1.a as '供应商',0 as '收入',表2.b as '支出,from A,B where 表2.c=3
) t
group by t.供应商

如果只是查询的话： select class,grade,class+grade as coad from 表 如果是要更新数据的话： update 表 set coad=class+grade

select 供应商, 收入,0 as 支出 from 表1 Uion select 供应商, 0 as 收入,支出 from 表2 联合查询，加分噢~~

select a.供应商,sum(a.收入)，sum(b.支出) from 表1 AS a,表2 AS b where 后面做个表连接，还有写条件吧

select 表1.a,sum(case when 表2,c=1 then 表2,b else 0 end)‘收入’,sum(case when 表2,c=3 then 表2,b else 0 end) ’支出‘ from a,b。具体自己整理吧，用这个case when语句就能解决！