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Window Functions

窗口函数：

  • row_number, rank, dense_rank, percent_rank, cume_disk, ntile, first_value, last_value, lead, lag
    • 函数名返回类型描述
    row_number(date,integer) String 赋予每一列一个唯一的行号。
    说明与解释：
           给每一行一个唯一的行号，从1开始。

    举例：
    select module, row_number() over() from tdh;
Result:
Streaming       1
TranswarpR      2
Hyperbase       3
Inceptor        4
select module, customer, row_number() over(order by customer) from tdh;
TranswarpR      2000000 1
Streaming       3000000 2
Hyperbase       5000000 3
Inceptor        9000000 4