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一个oracle语句不会写,该怎么解决

热度:52   发布时间:2016-04-24 05:35:50.0
一个oracle语句不会写
我有一张表里面name字段 时间time字段 
我想查询一下2010年这一年内每个月的name总数是多少怎么查询啊


------解决方案--------------------
tb你的那张表……
SQL code
select mm,nvl(quantity,0)from(select rownum mm from dual connect by rownum<=12)t1,(select to_char(time,'mm') mm,count(name) quantity from tbwhere to_char(time,'YYYY')='2010' group by to_char(time,'mm'))t2where t1.mm=t2.mm(+)order by t1.mm
------解决方案--------------------
1. 
select to_char(time,'yyyy-mm') mm,count(name) quantity from tb
where to_char(time,'YYYY')='2010' 
group by to_char(time,'mm')
order by to_char(time,'mm') 

2.
"select rownum mm from dual connect by rownum<=12" 这句算画蛇添足吗?
------解决方案--------------------
group by你的时间,是组查询
------解决方案--------------------
SQL code
select to_char(time,'yyyymm'),count(name) from your_tablewhere to_char(time,'YYYY')='2010'  group by to_char(time,'yyyymm')order by to_char(time,'yyyymm')
------解决方案--------------------
我建了一个简单的表,然后再里面插入了几条数据如下:
create table s(name varchar2(10),time date);
insert into s values('tt',to_date ( '2010-02-02' , 'YYYY-MM-DD' ) );

insert into s values('tt',to_date ( '2010-01-02' , 'YYYY-MM-DD' ) );
insert into s values('by',to_date ( '2010-03-02' , 'YYYY-MM-DD' ) );
insert into s values('gy',to_date ( '2010-04-02' , 'YYYY-MM-DD' ) );
insert into s values('ey',to_date ( '2010-05-02' , 'YYYY-MM-DD' ) );

insert into s values('tt',to_date ( '2010-01-02' , 'YYYY-MM-DD' ) );
insert into s values('by',to_date ( '2010-03-02' , 'YYYY-MM-DD' ) );
insert into s values('gy',to_date ( '2010-04-02' , 'YYYY-MM-DD' ) );
insert into s values('ey',to_date ( '2010-05-02' , 'YYYY-MM-DD' ) );
然后执行的查询语句是:
select to_char(time, 'mm'), name, count(1)
from s
 where to_char(time, 'yyyy') = 2010
 group by to_char(time, 'mm'), name;

结果就出来了,希望对你有帮助。
------解决方案--------------------
select to_char(time,'yyyymm'),count(distinct name) from tabl1 
where to_char(time,'yyyy')='2010'
group by to_char(time,'yyyymm')
------解决方案--------------------
实测,请参考:

------解决方案--------------------
select to_char(time,'yyyy-mm') mm,count(name) quantity from tb
where to_char(time,'YYYY')='2010'
group by to_char(time,'mm')
order by to_char(time,'mm')

------解决方案--------------------
探讨

实测,请参考:

------解决方案--------------------
SQL code
select to_char(time,'yyyy-mm')as  mm,count(name)  from tb_namewhere to_char(time,'YYYY')='2010'   group by to_char(time,'mm')order by to_char(time,'mm')  ----或者select to_char(time,'yyyy-mm')as  mm,count(name)  from tb_namewhere  to_char(time,'YYYY')='2010'   group by to_char(time,'yyyy-mm')order by to_char(time,'yyyy-mm')
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