求某字段最大值的一条记录的集合
create table testsql (name varchar(10),hours varchar(4),date varchar(8));
insert into testsql ('张三','8','20080101');
insert into testsql ('张三','10','20080102');
insert into testsql ('张三','9','20080103');
insert into testsql ('张三','7','20080104');
insert into testsql ('李四','7','20080104');
insert into testsql ('李四','1','20080105');
insert into testsql ('李四','2','20080106');
insert into testsql ('李四','3','20080107');
表定义：
TESTSQL表中记录每个员工每天工作的小时数
功能实现：
取出TESTSQL表中每个员工某天工作量最大的一条记录信息，结果期望如下
'张三','10','20080102'
'李四','7','20080104'
不能使用存储过程
[解决办法]
--首先SQL有问题，帮你改下（values）。
create table testsql (name varchar(10),hours varchar(4),date varchar(8));
insert into testsql values('张三','8','20080101');
insert into testsql values('张三','10','20080102');
insert into testsql values('张三','9','20080103');
insert into testsql values('张三','7','20080104');
insert into testsql values('李四','7','20080104');
insert into testsql values('李四','1','20080105');
insert into testsql values('李四','2','20080106');
insert into testsql values('李四','3','20080107');
--建议hours改为数字型好比较大小
--sql
Select t2.* from
(select name,char(max(int(hours))) as hours from testsql group by name) as t1,
testsql t2
where t1.name=t2.name
and t1.hours=t2.hours
[解决办法]
不明LZ在说什么
[解决办法]
