Question

SQL 求两个字段的百分比 怎么写？

数据表是这样的
车号 总人数 人数 百分比
111 23 12
222 161 21
我要是想求出人数和总人数的百分比请问要怎么写啊
补充问题：
总人数和人数是通过分组统计出来的，我的select 语句是
select chehao, sum(kaoshizong) as 总人数,sum(kaoshiguo) as 通过人数 from kaoshidui group by chehao

Answer 1

select chehao, sum(kaoshizong) as 总人数,sum(kaoshiguo) as 通过人数 ,round(sum(kaoshiguo)/sum(kaoshizong)*100,2) as 百分比 from kaoshidui group by chehao

--如果是sql2008，那么要给被除数加小数位，否则结果小于0时，只显示0
--以下为sql2008里的语句
select chehao, sum(kaoshizong) as 总人数,sum(kaoshiguo) as 通过人数 ,round(sum(kaoshiguo)/cast(sum(kaoshizong) as decimal(6,1))*100,2) as 百分比 from kaoshidui group by chehao

Answer 2

表结构是什么
是这样的话：
车号 总人数 人数 百分比
111 23 12
222 161 21
那需要 group by 吗？
那可能是一部分吧

Answer 3

试试这个，我没测：select chehao, sum(kaoshizong) as 总人数,sum(kaoshiguo) as 通过人数
trunc(sum(kaoshiguo)/sum(kaoshizong),2)

from kaoshidui group by chehao

Answer 4

select mz as '民族',count(*) as '人数',SUBSTRING (convert(varchar (20), (count(*)/80.00*100) ),1,4)+'%' as '比例' from ryxx group by mz