top的用法

select * from emp;

select top 2 * from emp;

select top 15 percent * from emp;

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--输出工资最高的前三个月员工所有信息
select top 3 * from emp order by sal desc; --从输出结果来看 先执行order by 后执行top

--工资从高到底排序 输出工资第4-6员工信息
select top3 * from emp where empno not in(select top 3 empno from emp order by sal desc)
order by sal desc

--工资从高到底排序 输出工资第7-9员工信息
select top3 * from emp where empno not in(select top 6 empno from emp order by sal desc)
order by sal desc

--工资从高到底排序 输出工资第10-12员工信息
select top3 * from emp where empno not in(select top 9 empno from emp order by sal desc)
order by sal desc

--工资从高到底排序 输出工资第12-14员工信息
select top3 * from emp where empno not in(select top 11 empno from emp order by sal desc)
order by sal desc

总结
假设每页显示n条记录 当前要显示的是第m页
表明是A 主键是A_id
select top n * from A_id where A_id not in (select top (m-1)*n A_id from emp)