rownum&row_number() over(order by column)区别

select rownum,row_number() over(order by id) row_numfrom tab1;--这个查询rownum 是查不出数据的Oracle的bug

select rownum,a.* from (select row_number() over (order by id) row_num from tab1) a;--可以查询出数据

over() 就相当于加上了一个条件

sum(sal) over(partition by deptno order by sal) 按部门累计薪酬

sum(sal) over (partition by deptno) 按部门求薪酬总和

sum(sal) over (order by sal) 累计薪酬

row_number 是Oracle提供的分析函数