Question

我需要创建一个查询来自两个表的数据的视图：

表＃1为Project（包含列ProjectID，Resource1，Resource2，Resource3，Resource4等。）
表＃2为ResourceTable（包含列ResourceID，AccountNO等。）

我需要根据AcccountNo查询ProjectID四种资源。

像

ProjectID, AccountNO for Resource1, AccountNO for Resource2, AccountNO for Resource3, AccountNO for Resource4

为此，我创建了以下查询 - 但它只返回一个资源的数据：

SELECT
    [ProjectID], [AccountNO]   
FROM 
    [dbo].[Project] 
INNER JOIN
    [dbo].[ResourceTable] ON [ProjectID].[ResourceID1] = [dbo].[ResourceTable].[AccountNO ]

输出：

ProjectID   AccountNoforResource1
----------------------------------
08SMA0001   NULL
10DL0051    29608529
10DL0052    NULL
10DL0053    NULL
10DL0055    29608233
10DL0058    29608233
11DL0011    NULL
11DL0013    29608233

但我需要所有资源帐号..

请帮我解决这个问题..

谢谢..

Answer 1

由于您键入了两次，我会假设[AccountNO ]（带空格）是实际的列名，如果有的话，这有点奇怪，但还行！

尝试以下查询。另请注意我如何Drupal\Core\Menu\LocalTaskManager->getDefinitions()使用as关键字：p，r1，r2等表格。aliased。 as关键字完全是可选的（我通常会将其删除但为了清晰起见而添加它）：

select [ProjectID], 
    r1.[AccountNO ] as [AccountNO_1],
    r2.[AccountNO ] as [AccountNO_2],
    r3.[AccountNO ] as [AccountNO_3],
    r4.[AccountNO ] as [AccountNO_4],
from [dbo].[Project] as p
left join [dbo].[ResourceTable] as r1 on p.[ResourceID1] = r1.[ResourceID]
left join [dbo].[ResourceTable] as r2 on p.[ResourceID2] = r2.[ResourceID]
left join [dbo].[ResourceTable] as r3 on p.[ResourceID3] = r3.[ResourceID]
left join [dbo].[ResourceTable] as r4 on p.[ResourceID4] = r4.[ResourceID]

从两个表中获取所需列的数据

1 个答案: