over 窗口函数使用
rank():返回行号,对比值重复时行号重复并间断, 即返回 1,2,2,4...
2.1 按照分区查看每行的个数
select *,rank() over(partition...2.2 按照分区和排序查看每行的数据
select *,rank() over(partition by department order by wages desc) cn from test1;
?...,对比值重复时行号重复但不间断, 即返回 1,2,2,3
注意他两的区别
4.2 dense_rank 窗口函数的显示
select *,dense_rank() over(partition by department...4.3 rank 窗口函数的显示
select *,rank() over(partition by department order by wages desc) cn from test1;
?...,即总排名连续
dense_rank() over(partition by department order by wages desc) as rn2,
-- 强制按列的结果排序,更像行号。