如何写百分比的语句

[ningweidong]

比如我有一个学生成绩表s
sno score
001 100
002 80
003 60
我会写考多少分的有多少人。
我想看考100分的占总数的百分比，或者看考60分以上的占总数的百分比
这个语句应该怎么写？我用的是sql server 2000

[--小F--]

select ltrim(cast( sum(case score when 100 then 1 else 0 end)*100.0/(select count(1) from tb) as dec(18,2)))+'%' from tb

[David8977]

select (select count(*) from #tb where score>60)/(select count(*) from #tb) 

[--小F--]

----------------------------------------------------------------
-- Author  :fredrickhu(小F，向高手学习)
-- Date    :2011-11-03 09:13:21
-- Version:
--      Microsoft SQL Server 2008 R2 (RTM) - 10.50.1617.0 (Intel X86) 
--	Apr 22 2011 11:57:00 
--	Copyright (c) Microsoft Corporation
--	Enterprise Evaluation Edition on Windows NT 6.1 <X64> (Build 7600: ) (WOW64)
--
----------------------------------------------------------------
--> 测试数据：[tb]
if object_id('[tb]') is not null drop table [tb]
go 
create table [tb]([sno] varchar(3),[score] int)
insert [tb]
select '001',100 union all
select '002',80 union all
select '003',60
--------------开始查询--------------------------
select
 ltrim(cast( sum(case score when 100 then 1 else 0 end)*100.0/(select count(1) from tb) as dec(18,2)))+'%' as [100分的百分比],
 ltrim(cast( sum(case when score>=60 then 1 else 0 end)*100.0/(select count(1) from tb) as dec(18,2)))+'%' as [60分以上的百分比]  
from
  tb
----------------结果----------------------------
/* 100分的百分比                                   60分以上的百分比
------------------------------------------ ------------------------------------------
33.33%                                     100.00%

(1 行受影响)

*/

[gw6328]

declare @t table(sno int,score int);
insert into @t select 1,100 union all
select 2,98 union all
select 3,60 union all
select 4,65;

select score/10*10,COUNT(1)*1.0/(select COUNT(1) from @t) from @t group by score/10

[jxjdzwang5555]

vfp：
use tt
count(*) to lnzong
count(*) to ln100 where score=100
lbfb= ln100/lnzong
?lbfb

我的sql代码:
declare @my100 decimal
set @my100 = (sele count(*) from tt where score=100)/(sele count(*) from tt )
/* i donot how to write */

[jxjdzwang5555]

可以declare @my100 decimal
set @my100 = (sele count(*) from tt where score=100)/(sele count(*) from tt )
吗？

[David8977]

declare @tb table
(sno int,score int)
declare @i decimal(18,4),@sum decimal(18,4),@count decimal(18,4)
insert @tb (sno,score) select 001,100 union select 002 ,80 union select 003,60
select @i=count(*) from @tb where score>60 
select @sum=count(*) from @tb
select @count=@i/@sum
select convert(varchar(20),@count*100)+'%' 

[jxjdzwang5555]

declare @tb table
(sno int,score int)
declare @i int,@sum int,@count decimal(18,4)
insert @tb (sno,score) select 1,100 union select 2 ,80 union select 3,60
select @i=count(*) from @tb where score>60
select @sum=count(*) from @tb
select @count=@i/@sum
select convert(varchar(20),@count*100)+'%'）

[pengxuan]

if object_id('tb','u') is not null
   drop table tb
go
create table tb
(
 sno varchar(10),
 score int
)
go
insert into tb
select '001',60 union all
select '002',60 union all
select '003',70 union all
select '004',70 union all
select '005',100 union all
select '006',100 union all
select '007',100
go
declare @cnt int
select @cnt=count(*) from tb
select [60分所占比例]=(select count(*)*100/@cnt from tb where score=60),
       [70分所占比例]=(select count(*)*100/@cnt from tb where score=70),
       [100分所占比例]=(select count(*)*100/@cnt from tb where score=100)
/*
60分所占比例     70分所占比例     100分所占比例
----------- ----------- -----------
28          28          42

(1 行受影响)
*/