SQL连接2个表
我想将两个表合并为一个表,并在其旁边添加一个计数器。我现在拥有的是SQL连接2个表,sql,Sql,我想将两个表合并为一个表,并在其旁边添加一个计数器。我现在拥有的是 SELECT [CUCY_DATA].*, [DIM].[Col1], [DIM].[Col2], (SELECT COUNT([Cut Counter]) FROM [MSD] WHERE [CUCY_DATA].[Cut Counter] = [MSD].[Cut Counter] ) AS [Nr Of Errors] FROM [CUCY_DATA] FULL JOIN [DIM] ON
SELECT [CUCY_DATA].*, [DIM].[Col1], [DIM].[Col2],
(SELECT COUNT([Cut Counter]) FROM [MSD]
WHERE [CUCY_DATA].[Cut Counter] = [MSD].[Cut Counter]
) AS [Nr Of Errors]
FROM [CUCY_DATA] FULL JOIN [DIM]
ON [CUCY_DATA].[Cut Counter] = [DIM].[Cut Counter]
通过这种方式插入数据,但如果值与空值不匹配,则插入空值。例如,我想要这个
表CUCY_数据
|_Cut Counter_|_Data1_|_Data2_|
| 1 | 12 | 24 |
| 2 | 13 | 26 |
| 3 | 10 | 20 |
| 4 | 11 | 22 |
桌子昏暗
|_Cut Counter_|_Col1_|_Col2_|
| 1 | 25 | 40 |
| 3 | 50 | 45 |
它们需要合并为:
|_Cut Counter_|_Data1_|_Data2_|_Col1_|_Col2_|
| 1 | 12 | 24 | 25 | 40 |
| 2 | 13 | 26 | 25 | 40 |
| 3 | 10 | 20 | 50 | 45 |
| 4 | 11 | 22 | 50 | 45 |
所以这是错误的:
|_Cut Counter_|_Data1_|_Data2_|_Col1__|_Col2__|
| 1 | 12 | 24 | 25 | 40 |
| 2 | 13 | 26 | NULL | NULL |
| 3 | 10 | 20 | 50 | 45 |
| 4 | 11 | 22 | NULL | NULL |
您好,Bob如果DIM表中没有相应的行,您如何获得col1和col2值?(第2行和第4行)。您的“错误”结果完全正确,这就是外部联接的作用