服务器相当于Oracle的CREATE OR REPLACE查看SQL

Question

在Oracle中，我可以重新创建一个单独的语句，视图，如下所示：

CREATE OR REPLACE VIEW MY_VIEW AS 
SELECT SOME_FIELD 
FROM SOME_TABLE 
WHERE SOME_CONDITIONS 

由于语法意味着，这将删除旧的视图和用我给出的任何定义重新创建它。

在SQL Server 2005中是否有相同的功能可以做同样的事情？

Answer 1

上述解决方案虽然可以完成任务，但可能会导致用户权限下降。我更愿意按照以下方式创建或替换视图或存储过程。

IF NOT EXISTS (SELECT * FROM sys.views WHERE object_id = OBJECT_ID(N'[dbo].[vw_myView]')) 
    EXEC sp_executesql N'CREATE VIEW [dbo].[vw_myView] AS SELECT ''This is a code stub which will be replaced by an Alter Statement'' as [code_stub]' 
GO 

ALTER VIEW [dbo].[vw_myView] 
AS 
SELECT 'This is a code which should be replaced by the real code for your view' as [real_code] 
GO 

Answer 2

您可以使用'IF EXISTS'来检查视图是否存在，如果存在则放弃。

 
IF EXISTS (SELECT TABLE_NAME FROM INFORMATION_SCHEMA.VIEWS 
     WHERE TABLE_NAME = 'MyView') 
    DROP VIEW MyView 
GO 

CREATE VIEW MyView 
AS 
    .... 
GO 

Answer 3

我通常使用这样的事：

if exists (select * from dbo.sysobjects 
    where id = object_id(N'dbo.MyView') and 
    OBJECTPROPERTY(id, N'IsView') = 1) 
drop view dbo.MyView 
go 
create view dbo.MyView [...] 

Answer 4

您可以使用ALTER更新视图，但是这比甲骨文命令不同，因为它只有在视图已经存在的作品。 DaveK的回答可能会更好，因为这将始终有效。

Answer 5

我用：

IF OBJECT_ID('[dbo].[myView]') IS NOT NULL 
DROP VIEW [dbo].[myView] 
GO 
CREATE VIEW [dbo].[myView] 
AS 

...

最近我加入了一些实用程序这种东西：

CREATE PROCEDURE dbo.DropView 
@ASchema VARCHAR(100), 
@AView VARCHAR(100) 
AS 
BEGIN 
    DECLARE @sql VARCHAR(1000); 
    IF OBJECT_ID('[' + @ASchema + '].[' + @AView + ']') IS NOT NULL 
    BEGIN 
    SET @sql = 'DROP VIEW ' + '[' + @ASchema + '].[' + @AView + '] '; 
    EXEC(@sql); 
    END 
END 

所以，现在我写

EXEC dbo.DropView 'mySchema', 'myView' 
GO 
CREATE View myView 
... 
GO 

我认为它我的脚本更具可读性

Answer 6

与SQL Server 2016，你有

DROP TABLE IF EXISTS [foo]; 

MSDN source

Answer 7

仅供参考来自SQL Server 2016 SP1+你可以使用CREATE OR ALTER VIEW语法。

MSDN CREATE VIEW：

CREATE [ OR ALTER ] VIEW [ schema_name . ] view_name [ (column [ ,...n ]) ] 
[ WITH <view_attribute> [ ,...n ] ] 
AS select_statement 
[ WITH CHECK OPTION ] 
[ ; ] 

或改变

有条件的改变，只有当它已经存在的视图。

Answer 8

它工作正常，我的SQL Server 2017年上：

USE MSSQLTipsDemo 
GO 
CREATE OR ALTER PROC CreateOrAlterDemo 
AS 
BEGIN 
SELECT TOP 10 * FROM [dbo].[CountryInfoNew] 
END 
GO 

https://www.mssqltips.com/sqlservertip/4640/new-create-or-alter-statement-in-