9.mysql排序

排序 

-- order by 字段

-- asc 从小到大排序，既升序

--desc 从大到小排序 ，既降序

select * from students where （age between 18 and 40）order by age  排序默认从小到大

select * from students where （age between 18 and 40）order by age asc  

select * from students where （age between 18 and 40）order by age desc 排序从大到小

--查询年龄在 18 到 34 之间的女性，身高从高到矮的排序

select * from students where age between 18 and 40  and gender = "女" order by height desc

-- order by 多个字段

--查询年龄在18到34岁之间的的女性，身高从高到矮排序，如果升高相同的情况下按照年龄从小到大排序

select * from students where age between 18 and 40  and gender = "女"  order by height desc,age desc,id desc

--年龄从小到大，身高从高到小

select * from students order by asc,hight desc