SQL 合并行

Question

我正在尝试分解并合并这样的表的结果。 (对于 Bingo!)我可以轻松地编写 CASE，以按第一个字母将列分开。然而，我最终显示的是空值，因为行被其 ID 视为不同的行。我在这里尝试了一些合并示例，但似乎被难住了。 ID 并不重要，我可以控制初始数据的收集方式。

ID  |  Number     |
====================
1   |      N6     | 
2   |      B22    |
3   |      B5     |
4   |      I9     |
5   |      N4     |


B  |  I  |  N  |  G  |  O  |
============================
B5 |  I9 | N4  |  -- | --  |
B22| --  | N6  |  -- | --  |

Answer 1

;WITH CTE AS
(
SELECT *,
       LEFT([Number],1) AS Letter,
       ROW_NUMBER() OVER (PARTITION BY LEFT([Number],1) 
                              ORDER BY CAST(SUBSTRING([Number],2,2) AS INT) ) AS RN
FROM Table1
)
SELECT 
    MAX(CASE WHEN Letter = 'B' THEN [Number] END) AS B,
    MAX(CASE WHEN Letter = 'I' THEN [Number] END) AS I,
    MAX(CASE WHEN Letter = 'N' THEN [Number] END) AS N,
    MAX(CASE WHEN Letter = 'G' THEN [Number] END) AS G,
    MAX(CASE WHEN Letter = 'O' THEN [Number] END) AS O
FROM CTE
GROUP BY RN

SQL Fiddle