使用SQL语句实现查询排序,顺序和倒序

SQL语句查询排序,顺序和倒序

SELECT 
	Company, OrderNumber 
FROM 
	Orders 
ORDER BY 
	Company DESC, OrderNumber ASC

#ASC升序，DESC倒序

1.以指定顺序返回查询结果（order by的asc为升序，desc为降序）

select ename,job,sal from emp
where deptno = 10
order by sal asc

2.多字段排序

select empno,deptno,sal,ename,job
from emp
order by deptno,sal desc

3.依据子串排序（SQL Sever使用substring(),其它用substr,而substr只有两个参数）

select ename,job
from emp
order by substring(job,len(job)-2,2)

4.排序时对null值处理

select ename,job,comm
from emp
order by 3

5.依据条件逻辑动态调整排序项

select ename,sal,job,comm
from emp
order by case when job = ‘SALESMAN' then comm else sal end