表
2008-01-01 A
2008-01-01 B
2008-01-02 C
2008-01-04 D
时间段
2008-01-01-2008-01-04
返回
2008-01-01 2
2008-01-02 1
2008-01-03 0
2008-01-04 1
2008-01-01 A
2008-01-01 B
2008-01-02 C
2008-01-04 D
时间段
2008-01-01-2008-01-04
返回
2008-01-01 2
2008-01-02 1
2008-01-03 0
2008-01-04 1
2008-01-01
2008-01-02
2008-01-03
2008-01-04
...然后用left join
(
cdate DATE constraint pk_calendar PRIMARY KEY
);insert into calendar values ('2008-01-01');
insert into calendar values ('2008-01-02');
insert into calendar values ('2008-01-03');
...
insert into calendar values ('2009-01-01');
from calendar c left jion tableA a on c.cdate=a.cdate
where c.cdate between '2008-01-01- and '2008-01-04'
group by c.cdate;
using()是什么函数?