看看这个类似的线程，我在其中写了一个sp以完成任务
将两个表（具有1-M关系）联接在一起，其中第二个表需要“展平”到一行
编辑。 更新的答案
create table `pivot` ( `id` int(11) not null auto_increment, `categoryid` int(11) default null, `processdate` date default null, `percentchange` int(11) default null, primary key (`id`)) engine=myisam auto_increment=9 default charset=latin1;insert into `pivot`(`id`,`categoryid`,`processdate`,`percentchange`) values (1,4,'2011-05-10',1);insert into `pivot`(`id`,`categoryid`,`processdate`,`percentchange`) values (2,4,'2011-05-11',22);insert into `pivot`(`id`,`categoryid`,`processdate`,`percentchange`) values (3,4,'2011-05-12',3);insert into `pivot`(`id`,`categoryid`,`processdate`,`percentchange`) values (4,7,'2011-05-10',4);insert into `pivot`(`id`,`categoryid`,`processdate`,`percentchange`) values (5,7,'2011-05-11',5);insert into `pivot`(`id`,`categoryid`,`processdate`,`percentchange`) values (6,12,'2011-05-10',6);insert into `pivot`(`id`,`categoryid`,`processdate`,`percentchange`) values (7,12,'2011-05-12',7);insert into `pivot`(`id`,`categoryid`,`processdate`,`percentchange`) values (8,4,'2011-05-13',12);delimiter //drop procedure if exists dynamic_view2//create procedure dynamic_view2(in sdate date,in edate date)begindeclare finish int default 0;declare cdate date;declare str varchar(10000) default "select categoryid,";declare curs cursor for select processdate from pivot where processdate between sdate and edate group by processdate;declare continue handler for not found set finish = 1;open curs;my_loop:loopfetch curs into cdate;if finish = 1 thenleave my_loop;end if;set str = concat(str, "max(case when processdate = '",cdate,"' then percentchange else null end) as `",cdate,"`,");end loop;close curs;set str = substr(str,1,char_length(str)-1);set @str = concat(str," from pivot group by categoryid");prepare stmt from @str;execute stmt;deallocate prepare stmt;end;//delimiter ;mysql> call dynamic_view2('2011-05-10','2011-05-13');+------------+------------+------------+------------+------------+| categoryid | 2011-05-10 | 2011-05-11 | 2011-05-12 | 2011-05-13 |+------------+------------+------------+------------+------------+| 4 | 1 | 22 | 3 | 12 || 7 | 4 | 5 | NULL | NULL || 12 | 6 | NULL | 7 | NULL |+------------+------------+------------+------------+------------+3 rows in set (0.00 sec)
