问题 :查询查询3月份,每人人加班的总时间?
数据库:mysql
创建表:
CREATE TABLE worked (
id VARCHAR(20) NOT NULL,
workname VARCHAR(20),
worktime INT(10),
workdate DATE
)
查询sql :
SELECT workname,SUM(worktime)FROM worked WHERE workdate BETWEEN '2012-3-1' AND '2012-3-31' GROUP BY workname
以上在mysql库中,做过测试可以成功