转载:https://blog.csdn.net/qq_25221835/article/details/82768375
转载:https://blog.csdn.net/qq_35449730/article/details/82955979(最近10条记录)
1.字段是varchar2类型即string,而其实存的是数字,这时候用order by排序
表数据与结构: salary 为 varchar 类型
create table TEST_ROW_NUMBER_OVER( id varchar(10) not null, name varchar(10) null, age varchar(10) null, salary varchar(10) null ); insert into TEST_ROW_NUMBER_OVER(id,name,age,salary) values(1,'a',10,'8000'); insert into TEST_ROW_NUMBER_OVER(id,name,age,salary) values(1,'a2',11,'6500'); insert into TEST_ROW_NUMBER_OVER(id,name,age,salary) values(2,'b',12,'13000'); insert into TEST_ROW_NUMBER_OVER(id,name,age,salary) values(2,'b2',13,'4500'); insert into TEST_ROW_NUMBER_OVER(id,name,age,salary) values(3,'c',14,'3000'); insert into TEST_ROW_NUMBER_OVER(id,name,age,salary) values(3,'c2',15,'20000'); insert into TEST_ROW_NUMBER_OVER(id,name,age,salary) values(4,'d',16,'30000'); insert into TEST_ROW_NUMBER_OVER(id,name,age,salary) values(5,'d2',17,'1800');
以 salary 降序
select id,name,age,salary from TEST_ROW_NUMBER_OVER order by cast(salary as integer) desc
2.查询数据库中最近的十条数据,并按时间升序进行排列
select *from ( select * from table1 order by datetime desc limit 0,10 ) order by datetime