tsql - 在 T-SQL 中是否有等效于 C#'s "throw;"来重新抛出异常？

Question

标题确实是这个问题的问题:T-SQL 中是否有与 C# 的“throw;”等价的东西？重新抛出异常？

在 C# 中，可以这样做:

try
{
    DoSomethingThatMightThrowAnException();
}
catch (Exception ex)
{
    // Do something with the exception
    throw; // Re-throw it as-is.
}

T-SQL 的 BEGIN CATCH 中有什么东西吗？功能一样吗？

Answer 1

您可以使用 RAISERROR。来自 MSDN documentation关于 RAISERROR:

BEGIN TRY
    -- RAISERROR with severity 11-19 will cause execution to 
    -- jump to the CATCH block
    RAISERROR ('Error raised in TRY block.', -- Message text.
               16, -- Severity.
               1 -- State.
               );
END TRY
BEGIN CATCH
    DECLARE @ErrorMessage NVARCHAR(4000);
    DECLARE @ErrorSeverity INT;
    DECLARE @ErrorState INT;

    SELECT @ErrorMessage = ERROR_MESSAGE(),
           @ErrorSeverity = ERROR_SEVERITY(),
           @ErrorState = ERROR_STATE();

    -- Use RAISERROR inside the CATCH block to return 
    -- error information about the original error that 
    -- caused execution to jump to the CATCH block.
    RAISERROR (@ErrorMessage, -- Message text.
               @ErrorSeverity, -- Severity.
               @ErrorState -- State.
               );
END CATCH;

编辑:

这与 c# 的 throw 不是一回事或 throw ex .正如@henrikstaunpoulsen 指出的那样，您不会在新错误中获得原始错误编号(RAISERROR 可以使用的编号受到限制)。您必须使用某种约定并从消息中解析信息(如果可用)。

MSDN有一篇文章 Using TRY...CATCH in Transact-SQL我使用了一些代码来创建下面的测试:

use test;
GO

IF OBJECT_ID (N'usp_RethrowError',N'P') IS NOT NULL
    DROP PROCEDURE usp_RethrowError;
GO

CREATE PROCEDURE usp_RethrowError AS
    IF ERROR_NUMBER() IS NULL
        RETURN;

    DECLARE 
        @ErrorMessage    NVARCHAR(4000),
        @ErrorNumber     INT,
        @ErrorSeverity   INT,
        @ErrorState      INT,
        @ErrorLine       INT,
        @ErrorProcedure  NVARCHAR(200);

    SELECT 
        @ErrorNumber = ERROR_NUMBER(),
        @ErrorSeverity = ERROR_SEVERITY(),
        @ErrorState = ERROR_STATE(),
        @ErrorLine = ERROR_LINE(),
        @ErrorProcedure = ISNULL(ERROR_PROCEDURE(), '-');

    SELECT @ErrorMessage = 
        N'Error %d, Level %d, State %d, Procedure %s, Line %d, ' + 
            'Message: '+ ERROR_MESSAGE();

    RAISERROR 
        (
        @ErrorMessage, 
        @ErrorSeverity, 
        @ErrorState,               
        @ErrorNumber,    -- parameter: original error number.
        @ErrorSeverity,  -- parameter: original error severity.
        @ErrorState,     -- parameter: original error state.
        @ErrorProcedure, -- parameter: original error procedure name.
        @ErrorLine       -- parameter: original error line number.
        );
GO

PRINT 'No Catch'
DROP TABLE XXXX

PRINT 'Single Catch'
BEGIN TRY
    DROP TABLE XXXX
END TRY
BEGIN CATCH
    EXEC usp_RethrowError;
END CATCH;

PRINT 'Double Catch'
BEGIN TRY
    BEGIN TRY
        DROP TABLE XXXX
    END TRY
    BEGIN CATCH
        EXEC usp_RethrowError;
    END CATCH;
END TRY
BEGIN CATCH
    EXEC usp_RethrowError;
END CATCH;

产生以下输出:

No Catch
Msg 3701, Level 11, State 5, Line 3
Cannot drop the table 'XXXX', because it does not exist or you do not have permission.
Single Catch
Msg 50000, Level 11, State 5, Procedure usp_RethrowError, Line 25
Error 3701, Level 11, State 5, Procedure -, Line 7, Message: Cannot drop the table 'XXXX', because it does not exist or you do not have permission.
Double Catch
Msg 50000, Level 11, State 5, Procedure usp_RethrowError, Line 25
Error 50000, Level 11, State 5, Procedure usp_RethrowError, Line 25, Message: Error 3701, Level 11, State 5, Procedure -, Line 16, Message: Cannot drop the table 'XXXX', because it does not exist or you do not have permission.