Question

我想知道如何在排序表中显示列内容的出现次数

这是我的表REF内容，有两列：

POSITION| MYVAL
---------------
   1    | U
   2    | U
   3    | B
   4    | R
   5    | R
   6    | R
   7    | C

我想有这样的结果表（引入一个NO_OCCURENCE列，显示MYVAL内容的出现次数）：

  POSITION | NO_OCCURENCE| MYVAL
  --------------------------------
     1     |     1       |   U
     2     |     2       |   U
     3     |     1       |   B
     4     |     1       |   R
     5     |     2       |   R
     6     |     3       |   R
     7     |     1       |   C

我如何在ORACLE SQL中执行此操作？

此致

Answer 1

您可以使用窗口功能：

select position,
       row_number() over (partition by myval order by position) as no_occurence, 
       myval
from the_table
order by position, myval;

Answer 2

使用排名功能。请参阅RANK, DENSE_RANK, FIRST and LAST Analytic Functions。

SELECT POSITION, 
       DENSE_RANK() OVER (PARTITION BY MYVAL ORDER BY POSITION ASC) AS NO_OCCURENCE, 
       MYVAL
FROM Table

ORACLE SQL：如何显示已排序表中列内容的出现次数？

2 个答案: