分析函数

分析函数
row_number() over(partition by a order by b) order_id
dense_rank() over(partition by a order by b) order_id
rank() over()(partition by a order by b) order_id

row_number dense_rank rank

2001 1 1 1

2002 2 2 2

2002 3 2 2

2003 4 3 4