try catch
可以很容易捕捉异常了今天大概学习看了下归纳下要点如下基本使用方法BEGIN TRY
{ sql_statement |
statement_block }
END TRY
BEGIN CATCH
{ sql_statement |
statement_block }
END CATCH
和普通语言异常处理使用方法差不多但要注意是SQL SERVER只捕捉那些不是严重异常当比如数据库不能连接等这类异常时是不能捕捉
个例子:BEGIN TRYDECLARE @X INT
-- Divide by zero to generate Error
SET @X = 1/0
PRINT 'Command after error in TRY block'
END TRY
BEGIN CATCH
PRINT 'Error Detected'
END CATCH
PRINT 'Command after TRY/CATCH blocks'
另外try catch可以嵌套Begin TRY
delete from GrandParent where Name = 'John Smith'
pr
'GrandParent deleted successfully'End Try
Begin Catch
Pr
'Error Deleting GrandParent Record'Begin Try
delete from Parent where GrandParentID =
(select distinct ID from GrandParent where Name = 'John Smith')
Pr
'Parent Deleted Successfully'End Try
Begin Catch
pr
'Error Deleting Parent'Begin Try
delete from child where ParentId =
(select distinct ID from Parent where GrandParentID =
(select distinct ID from GrandParent where Name = 'John Smith'))
pr
'Child Deleted Successfully'End Try
Begin Catch
Pr
'Error Deleting Child'End Catch
End Catch
End Catch
另外
SQL SERVER 2005在异常机制中提供了error类思路方法方便调试现摘抄如下比较简单不予以解释ERROR_NUMBER
: Returns a number associated with the error.ERROR_SEVERITY: Returns the severity of the error.ERROR_STATE: Returns the error state number associated with the error.ERROR_PROCEDURE: Returns the name of the stored procedure or trigger in which the error occurred.ERROR_LINE: Returns the line number inside the failing routine that caused the error. ERROR_MESSAGE: Returns the complete text of the error message. The text 
s the values supplied for any substitutable parameters, such as lengths, object names, or times. 最后举例子如下使用了error类思路方法BEGIN TRYDECLARE @X INT
-- Divide by zero to generate Error
SET @X = 1/0
PRINT 'Command after error in TRY block'
END TRY
BEGIN CATCH
PRINT 'Error Detected'
SELECT ERROR_NUMBER
ERNumber,ERROR_SEVERITY
Error_Severity,ERROR_STATE
Error_State,ERROR_PROCEDURE
Error_Procedure,ERROR_LINE
Error_Line,ERROR_MESSAGE
Error_MessageEND CATCH
PRINT 'Command after TRY/CATCH blocks'
最后输出Error Detected
Err_Num Err_Sev Err_State Err_Proc Err_Line Err_Msg
------- ------- --------- -------------------- --------- --------------------------------
8134 16 1 NULL 4 Divide by zero error encountered.
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