如果Count（distinct）为0，则显示数据

Question

SQL Server 2008

SQL查询显示IP地址（如果存在）

SELECT [IP_ADDR1_TEXT], COUNT(distinct [IP_ADDR1_TEXT]) as Instances
FROM sem_computer, [dbo].[V_SEM_COMPUTER]
WHERE sem_computer.COMPUTER_ID = [dbo].[V_SEM_COMPUTER].COMPUTER_ID
AND [IP_ADDR1_TEXT] = '10.10.10.10'
GROUP BY [IP_ADDR1_TEXT]

输出

IP_ADDR1_TEXT   Instances
10.10.10.10         1

如果IP地址计数为0，则输出为空。

如何修改查询，以便实例输出0，在不存在的IP地址旁边，即

SELECT [IP_ADDR1_TEXT], COUNT(distinct [IP_ADDR1_TEXT]) as Instances
FROM sem_computer, [dbo].[V_SEM_COMPUTER]
WHERE sem_computer.COMPUTER_ID = [dbo].[V_SEM_COMPUTER].COMPUTER_ID
AND [IP_ADDR1_TEXT] = '10.10.10.11'
GROUP BY [IP_ADDR1_TEXT]

应输出

IP_ADDR1_TEXT   Instances
10.10.10.11         0

编辑

VIEW的屏幕截图

IP_ADDR1_TEXT是ALIAS to

色谱柱 CAST（IP_ADDR1＆lt; 0 THEN 0xFFFFFFFF + IP_ADDR1 ELSE IP_ADDR1 END / 256/256/256＆amp; 0xFF AS VARCHAR）+＆＃39;。＆＃39; + CAST（IP_ADDR1＆lt; 0 THEN 0xFFFFFFFF + IP_ADDR1 ELSE IP_ADDR1 END / 256/256＆amp; 0xFF AS VARCHAR）+＆＃39;。＆＃39; + CAST（IP_ADDR1＆lt; 0 THEN 0xFFFFFFFF + IP_ADDR1 ELSE IP_ADDR1 END / 256＆amp; 0xFF AS VARCHAR）+＆＃39;。＆＃39; + CAST（IP_ADDR1＆lt; 0 THEN 0xFFFFFFFF + IP_ADDR1 ELSE IP_ADDR1 END＆amp; 0xFF AS VARCHAR）

Answer 1

SELECT [IP_ADDR1_TEXT], COALESCE(COUNT(distinct [IP_ADDR1_TEXT]),0) as Instances
FROM sem_computer LEFT JOIN [dbo].[V_SEM_COMPUTER]
  ON sem_computer.COMPUTER_ID = [dbo].[V_SEM_COMPUTER].COMPUTER_ID
AND [IP_ADDR1_TEXT] = '10.10.10.11'
GROUP BY [IP_ADDR1_TEXT]

Answer 2

也许试试这个：

SELECT [IP_ADDR1_TEXT], COUNT(distinct [IP_ADDR1_TEXT]) as Instances
FROM sem_computer
Left JOin [dbo].[V_SEM_COMPUTER] On sem_computer.COMPUTER_ID = [dbo].[V_SEM_COMPUTER].COMPUTER_ID
WHERE [IP_ADDR1_TEXT] = '10.10.10.10'
GROUP BY [IP_ADDR1_TEXT]