这个SQL怎么写？

[sybase2000]

有一个表，结构如下：

rq bz je
2010-1-1 1 500.00
2010-1-1 1 800.00
2010-1-5 2 30.00
2010-1-5 2 70.00
2010-1-5 2 100.00
2010-1-5 4 20.00
2010-1-6 6 1000.00

按bz列进行归类，找出表中共有多少个不同值的bz列

结果应该为4

[w3329307]

坐着看看

[andy_liucj]

select count(distinct bz) from tb

[--小F--]

SELECT COUNT(DISTINCT BZ) FROM TB

[wancheng76]

select count(bz) from tb group by bz

[Barton]

select count(distinct bz) from tb

[lijian8552]

select count(distinct bz) from tb

[xp880619]

select count(distinct bz)
from tb

[dark123y]

select count(distinct bz) from ..

[cutebear2008]

select count(*) from (select distinct bz from tb) a

[心灵的深处总是孤单的]

select count(distinct bz)
from tb

[jetvan]

SELECT COUNT(DISTINCT BZ) FROM TB

[rfq]

select count(distinct bz) from tb

[liang145]

select count(*) from (select distinct bz from #Test) as s

[林少1024]

[Quote=引用 4 楼 wancheng76 的回复:]

select count(bz) from tb group by bz
[/Quote]


这个也可以，你要多学几种方法咯。