显示分为几列的数据

Question

我有一个数据列表，我想显示它们而不管其顺序如何，而是按列的特定顺序显示，例如3

id
1
2
3
4
5
6
7
8
9
10
11
12
13
14


id1 id2 id3
1   6   11
2   7   12
3   8   13
4   9   14
5   10  NULL

Final result

Answer 1

您可以使用窗口函数和条件聚合：

select max(case when seqnum % 3 = 1 then id end),
       max(case when seqnum % 3 = 2 then id end),
       max(case when seqnum % 3 = 0 then id end)       
from (select t.*,
             row_number() over (order by (select null)) as seqnum
      from t
     ) t
group by (seqnum - 1) / 3

Answer 2

这很棘手。一种方法是对ROW_NUMBER使用两次调用，一个用于行位置，另一个用于列位置。这里的逻辑是，每行都属于一个组，该组随着id增加5的倍数而翻转，而该列由id值代表的5的倍数确定。

WITH cte AS (
    SELECT id,
        (ROW_NUMBER() OVER (ORDER BY id) - 1) / 5 AS rn1,
        (ROW_NUMBER() OVER (ORDER BY id) - 1) % 5 AS rn2
    FROM yourTable
)

SELECT
    rn2,
    MAX(CASE WHEN rn1 = 0 THEN id END) AS id1,
    MAX(CASE WHEN rn1 = 1 THEN id END) AS id2,
    MAX(CASE WHEN rn1 = 2 THEN id END) AS id3
FROM cte
GROUP BY
    rn2
ORDER BY
    rn2;

Demo