根据另一个列排序生成新列 - SQL

Question

您好，我正在尝试在 Teradata V14 sql 中进行。我的来源 table 是这样的：

acc  col1  col2

100  12     13
100  13     14
100  17     23
100  22     109
100  23     110
100  29     130

我的目标 table 应该是：

New_Col1 New_Col2 Acc col1 col2

1          1      100  12     13
2          1      100  13     14
3          2      100  17     23
4          3      100  22     109
5          3      100  23     110
6          4      100  29     130

New_Col1 - 行号 New_Col2 - 如果 col1 和 col2 在序列中相同的值应该是 New_COl2。否则应生成新的序列号任何人都可以帮助我实现这一目标。

Answer 1

看来第二个新列就是col1是否有顺序。您可以使用 row_number():

select row_number() over (partition by acc order by col1),
       dense_rank() over (partition by acc order by grp),
       acc, col1, col2
from (select t.*,
             (col1 - row_number() over (partition by acc order by col1)) as grp
      from t
     ) t;

Answer 2

您需要嵌套的 OLAP 函数：

SELECT dt.*,
   sum(flag) 
   OVER (PARTITION BY acc
         ORDER BY new_col1
         ROWS UNBOUNDED PRECEDING)
FROM
 (
   SELECT t.*,
      ROW_NUMBER() OVER (PARTITION BY acc ORDER BY col1, col2) AS new_col1,
      CASE WHEN col1 = MIN(col1) -- col1 is sequential
                       OVER (PARTITION BY acc
                             ORDER BY col1,col2
                             ROWS BETWEEN 1 PRECEDING AND 1 PRECEDING) + 1
            AND col2 = MIN(col2) -- col2 is sequential
                       OVER (PARTITION BY acc
                             ORDER BY col1,col2
                             ROWS BETWEEN 1 PRECEDING AND 1 PRECEDING) + 1
           THEN 0 -- will be assigned to the previous group
           ELSE 1 -- will be assigned to a new group
      END AS flag   
   FROM tab AS t
 ) AS dt

根据另一个列排序生成新列 - SQL

Generate new column based on another column sequencing - SQL

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teradata