如果不存在，工作的CREATE VIEW会给出语法错误

Question

对于统计报告，我有一个简单的CREATE VIEW脚本，该脚本本身可以工作：

CREATE VIEW [dbo].[Report888View] AS
SELECT TOP 5000 pv.[AgentName] AS 'Label',
        COUNT(*) AS 'NumData1'
FROM [FullmaktsnodenProcess].[dbo].[ProcessingView] pv          
JOIN [Fullmaktsnoden].[dbo].[POAs] p ON (pv.FullmaktskollenPOAId=p.FullmaktskollenPoaId)
JOIN [Fullmaktsnoden].[dbo].[ReceivedPOAs] rp ON (p.Id=rp.Id)
WHERE pv.ErrorCode='888' and pv.Status <> 9
GROUP BY pv.[AgentName]
ORDER BY NumData1 DESC;

当我在SQL Server 2016上进行开发时，不能保证在客户安装上使用，因此不能使用CREATE或ALTER。

因此，我认为应该将其放入标准的“不存在”中：

IF NOT EXISTS
(
    SELECT [name]
    FROM sys.views
    WHERE [name] = 'Report888View'
)
BEGIN
    CREATE VIEW [dbo].[Report888View] AS
    SELECT TOP 5000 pv.[AgentName] AS 'Label',
            COUNT(*) AS 'NumData1'
    FROM [FullmaktsnodenProcess].[dbo].[ProcessingView] pv          
    JOIN [Fullmaktsnoden].[dbo].[POAs] p ON (pv.FullmaktskollenPOAId=p.FullmaktskollenPoaId)
    JOIN [Fullmaktsnoden].[dbo].[ReceivedPOAs] rp ON (p.Id=rp.Id)
    WHERE pv.ErrorCode='888' and pv.Status <> 9
    GROUP BY pv.[AgentName]
    ORDER BY NumData1 DESC;
END

（无论是否使用BEGIN-END，我都尝试过）

但是，此代码给我“语法错误：'CREATE VIEW'必须是批处理中的唯一语句。” 我看不到我在做什么错...

编辑：更正了'NumData1'-> NumData1

Answer 1

相反，如果存在视图，则应该先删除该视图，并且需要使用GO语句来分隔批处理

if exists(select 1 from sys.views where name='Report888View' and type='v')
drop view Report888View;

go

CREATE VIEW [dbo].[Report888View] AS
    SELECT TOP 5000 pv.[AgentName] AS 'Label',
            COUNT(*) AS 'NumData1'
    FROM [FullmaktsnodenProcess].[dbo].[ProcessingView] pv          
    JOIN [Fullmaktsnoden].[dbo].[POAs] p ON (pv.FullmaktskollenPOAId=p.FullmaktskollenPoaId)
    JOIN [Fullmaktsnoden].[dbo].[ReceivedPOAs] rp ON (p.Id=rp.Id)
    WHERE pv.ErrorCode='888' and pv.Status <> 9
    GROUP BY pv.[AgentName]
    ORDER BY 'NumData1' DESC;

Answer 2

你可以试试这个

对于SQL Server 2016+

    CREATE OR ALTER VIEW dbo.Report888View AS
    SELECT TOP 5000 pv.[AgentName] AS 'Label',
            COUNT(*) AS 'NumData1'
    FROM [FullmaktsnodenProcess].[dbo].[ProcessingView] pv          
    JOIN [Fullmaktsnoden].[dbo].[POAs] p ON (pv.FullmaktskollenPOAId=p.FullmaktskollenPoaId)
    JOIN [Fullmaktsnoden].[dbo].[ReceivedPOAs] rp ON (p.Id=rp.Id)
    WHERE pv.ErrorCode='888' and pv.Status <> 9
    GROUP BY pv.[AgentName]
    ORDER BY NumData1 DESC;

对于以下SQL Server 2016

IF EXISTS ( SELECT * FROM SYS.VIEWS WHERE NAME = 'Report888View' )
BEGIN
     DROP VIEW dbo.Report888View        
END


---- OR YOU MAY USE THIS TO DROP VIEW

IF (SELECT OBJECT_ID('dbo.Report888View') )  IS NOT NULL
BEGIN
   DROP VIEW dbo.Report888View          
END

GO

CREATE VIEW dbo.Report888View AS
SELECT TOP 5000 pv.[AgentName] AS 'Label',
    COUNT(*) AS 'NumData1'
FROM [FullmaktsnodenProcess].[dbo].[ProcessingView] pv          
JOIN [Fullmaktsnoden].[dbo].[POAs] p ON (pv.FullmaktskollenPOAId=p.FullmaktskollenPoaId)
JOIN [Fullmaktsnoden].[dbo].[ReceivedPOAs] rp ON (p.Id=rp.Id)
WHERE pv.ErrorCode='888' and pv.Status <> 9
GROUP BY pv.[AgentName]
ORDER BY NumData1 DESC;

Answer 3

如果视图中存在该视图，并且您不希望这些lsot 9so仅在确实不存在时创建视图），则需要使用“动态”语句，例如：

IF NOT EXISTS
(
    SELECT [name]
    FROM sys.views
    WHERE [name] = 'Report888View'
)
BEGIN

    DECLARE @SQL nvarchar(MAX);
    SET @SQL = N'
    CREATE VIEW [dbo].[Report888View] AS
    SELECT TOP 5000 pv.[AgentName] AS ''Label'',
            COUNT(*) AS ''NumData1''
    FROM [FullmaktsnodenProcess].[dbo].[ProcessingView] pv          
    JOIN [Fullmaktsnoden].[dbo].[POAs] p ON (pv.FullmaktskollenPOAId=p.FullmaktskollenPoaId)
    JOIN [Fullmaktsnoden].[dbo].[ReceivedPOAs] rp ON (p.Id=rp.Id)
    WHERE pv.ErrorCode=''888'' and pv.Status <> 9
    GROUP BY pv.[AgentName]
    ORDER BY NumData1 DESC;';

    EXEC sp_executesql @SQL;

END

由sp_executesql运行的SQL的范围将在单独的批中，因此不会产生错误。 另请注意，我“解决”了您的ORDER BY 。 'NumData1和NumData1完全不同； 一个是文字字符串 ，另一个是SELECT定义的列的别名。

另外，如果您要CREATE或ALTER视图，无论它是否存在，都可以使用表达式来更改关键字的值：

DECLARE @SQL nvarchar(MAX);

SET @SQL = CASE WHEN  EXISTS(SELECT [name] FROM sys.views WHERE [name] = N'Report888View') THEN N'ALTER' ELSE N'CREATE' END + N' VIEW [dbo].[Report888View] AS
SELECT TOP 5000 pv.[AgentName] AS ''Label'',
        COUNT(*) AS ''NumData1''
FROM [FullmaktsnodenProcess].[dbo].[ProcessingView] pv          
JOIN [Fullmaktsnoden].[dbo].[POAs] p ON (pv.FullmaktskollenPOAId=p.FullmaktskollenPoaId)
JOIN [Fullmaktsnoden].[dbo].[ReceivedPOAs] rp ON (p.Id=rp.Id)
WHERE pv.ErrorCode=''888'' and pv.Status <> 9
GROUP BY pv.[AgentName]
ORDER BY NumData1 DESC;';

EXEC sp_executesql @SQL;

Answer 4

尝试这样的事情：

IF NOT EXISTS (SELECT * FROM sys.views WHERE object_id = OBJECT_ID(N'[dbo].[MyView]'))
EXEC dbo.sp_executesql @statement = N'CREATE VIEW [dbo].[MyView]
AS
...
'