一个统计以往数据的SQL。

CREATE TABLE IF NOT EXISTS `income` (
  `id` int(11) NOT NULL,
  `idate` date DEFAULT NULL,
  `money` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `idate` (`idate`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

select a.idate ,sum(b.money) as num
from income as a left join income as b 
on b.idate<=a.idate group by a.idate order by a.idate 

SELECT id, idate, (@rowNum := @rowNum + money) AS total FROM income, (
SELECT (@rowNum := ifnull( (SELECT sum( money ) FROM income WHERE id <=0 ) , 0)))b ORDER BY id limit 0,30