求教一条sql 写法，在线等结贴 立刻给分

Question

问题如下： 有一张表table1   里面字段数据
ID           date                            key
1      2009-10-23 16:57:43                  123
2      2009-08-21 8:57:43                   123
3      2009-08-21 16:57:43                  456
4      2009-10-23 11:57:43                  123
5      2009-10-23 10:57:43                  456
3      2009-08-21  5:57:43                  456
想取出数据分析 按照日期，key相同分组查询数据，取出id数量的信息显示到页面上。 比如上面数据应该显示
日期            数量       key   
2009-08-21      1           123 
2009-08-21      2           456
2009-10-23      2           123
2009-10-23      1           456求教sql应该怎么写，在线等结贴

Answer 1

select sum(1),date,key from table1 group by date,key 

Answer 2

select substr(date,1,10),count(1),key
from table1
group by substr(date,1,10),key

Answer 3

select to_char(date,'yyyy-mm-dd'), count(1), key from t group by to_char(date,'yyyy-mm-dd'), key;

Answer 4

select trunc(date,'dd'),count(1),key
from tabe1
group by trunc(date,'dd'),key

Answer 5

select to_char(date,'yyyy-mm-dd'),count(1),key  from table1
group by to_char(date,'yyyy-mm-dd'),key