Question

问题：如果我将创建过程中不存在的IF作为外部名称语句添加，我会收到语法错误...为什么？如果我单独运行它们，两种语句都可以正常工作......

IF  NOT EXISTS 
(
    SELECT * FROM sys.objects 
    WHERE object_id = OBJECT_ID(N'PriceSum') 
    AND type in (N'P', N'PC')
)
CREATE PROCEDURE PriceSum(@sum int OUTPUT)
     AS EXTERNAL NAME MyFirstUdp.[SQL_CLRdll.MySQLclass].PriceSum

Answer 1

因为CREATE PROCEDURE必须是批处理中的第一个语句。

首先删除proc或使用动态SQL

IF  NOT EXISTS 
(
    SELECT * FROM sys.objects 
    WHERE object_id = OBJECT_ID(N'PriceSum') 
    AND type in (N'P', N'PC')
)
exec('CREATE PROCEDURE PriceSum(@sum int OUTPUT)
     AS EXTERNAL NAME MyFirstUdp.[SQL_CLRdll.MySQLclass].PriceSum')

你也可以颠倒逻辑

    IF  EXISTS 
    (
        SELECT * FROM sys.objects 
        WHERE object_id = OBJECT_ID(N'PriceSum') 
        AND type in (N'P', N'PC')
    )

    DROP PROCEDURE PriceSum
    GO --this ends the batch, so the create statement below is fine

    CREATE PROCEDURE PriceSum(@sum int OUTPUT)
AS EXTERNAL NAME MyFirstUdp.[SQL_CLRdll.MySQLclass].PriceSum
  GO

Answer 2

尝试

IF  NOT EXISTS 
(
    SELECT * FROM sys.objects 
    WHERE object_id = OBJECT_ID(N'PriceSum') 
    AND type in (N'P', N'PC')
)

EXEC ('CREATE PROCEDURE PriceSum(@sum int OUTPUT)
     AS EXTERNAL NAME MyFirstUdp.[SQL_CLRdll.MySQLclass].PriceSum')

我认为它不喜欢CREATE PROCEDURE之前和同一批次中的内容。

SQL语法错误CREATE PROCEDURE AS EXTERNAL

2 个答案: