RAISERROR |
THROW |
Version of the Sql Server in which it is introduced? |
Introduced in SQL SERVER 7.0. And as per BOL, Microsoft is suggesting to start using THROW statement instead of RAISERROR in New Applications.
RAISERROR can’t be used in the Sql Server 2014’s Natively compiled Stored Procedures. |
Introduced in SQL SERVER 2012. THROW statement seems to be simple and easy to use than RAISERROR.
THROW statement can be used in the Sql Server 2014’s Natively Compiled Stored Procedure. |
SYNTAX |
RAISERROR
( { error_number | message
| @local_variable }
{ ,severity ,state }
[ ,argument [ ,...n ] ] )
[ WITH option [ ,...n ] ]
|
THROW
[ { error_number
| @local_variable },
{ message | @local_variable },
{ state | @local_variable } ]
[ ; ]
|
Can re-throw the original exception that invoked the CATCH block? |
NO. It always generates new exception and results in the loss of the original exception details. Below example demonstrates this:
BEGIN TRY
DECLARE @result INT
--Generate divide-by-zero error
SET @result = 55/0
END TRY
BEGIN CATCH
--Get the details of the error
--that invoked the CATCH block
DECLARE
@ErMessage NVARCHAR(2048),
@ErSeverity INT,
@ErState INT
SELECT
@ErMessage = ERROR_MESSAGE(),
@ErSeverity = ERROR_SEVERITY(),
@ErState = ERROR_STATE()
RAISERROR (@ErMessage,
@ErSeverity,
@ErState )
END CATCH
RESULT:
Msg 50000, Level 16, State 1, Line 19
Divide by zero error encountered.
NOTE:The actual line number of the code which generated Divided By Zero error here is 4, but the exception message returned by RAISERROR is showiung it as 19. Also the error number corresponding to divide by zero error is 8134 in the SYS.Messages table, but the one returned by RAISERROR is 50000. |
YES. To Re-THROW the original exception caught in the TRY Block, we can just specify the THROW statement without any parameters in the CATCH block. Below example demonstrates this:
BEGIN TRY
DECLARE @result INT
--Generate divide-by-zero error
SET @result = 55/0
END TRY
BEGIN CATCH
THROW
END CATCH
RESULT:
Msg 8134, Level 16, State 1, Line 4
Divide by zero error encountered.
With above example it is clear that THROW statement is very simple for RE-THROWING the exception. And also it returns correct error number and line number. |
Causes the statement batch to be ended? |
Example 1: In the below Batch of statements the PRINT statement after RAISERROR statement will be executed.
BEGIN
PRINT 'BEFORE RAISERROR'
RAISERROR('RAISERROR TEST',16,1)
PRINT 'AFTER RAISERROR'
END
RESULT:
BEFORE RAISERROR
Msg 50000, Level 16, State 1, Line 3
RAISERROR TEST
AFTER RAISERROR
Example 2: In the below example all the statement’s after RAISERROR statement are executed.
BEGIN TRY
DECLARE @RESULT INT = 55/0
END TRY
BEGIN CATCH
PRINT 'BEFORE RAISERROR';
--Get the details of the error
--that invoked the CATCH block
DECLARE
@ErMessage NVARCHAR(2048),
@ErSeverity INT,
@ErState INT
SELECT
@ErMessage = ERROR_MESSAGE(),
@ErSeverity = ERROR_SEVERITY(),
@ErState = ERROR_STATE()
RAISERROR (@ErMessage,
@ErSeverity,
@ErState )
PRINT 'AFTER RAISERROR'
END CATCH
PRINT 'AFTER CATCH'
RESULT:
BEFORE RAISERROR
Msg 50000, Level 16, State 1, Line 19
Divide by zero error encountered.
AFTER RAISERROR
AFTER CATCH |
Example 1: In the below Batch of statements the PRINT statement after THROW statement will not executed.
BEGIN
PRINT 'BEFORE THROW';
THROW 50000,'THROW TEST',1
PRINT 'AFTER THROW'
END
RESULT:
BEFORE THROW
Msg 50000, Level 16, State 1, Line 3
THROW TEST
Example 2: In the below example no PRINT statement’s after THROW statement are executed.
BEGIN TRY
DECLARE @RESULT INT = 55/0
END TRY
BEGIN CATCH
PRINT 'BEFORE THROW';
THROW;
PRINT 'AFTER THROW'
END CATCH
PRINT 'AFTER CATCH'
RESULT:
BEFORE THROW
Msg 8134, Level 16, State 1, Line 2
Divide by zero error encountered. |
CAN SET SEVERITY LEVEL? |
YES. The severity parameter specifies the severity of the exception. |
NO. There is no severity parameter. The exception severity is always set to 16. (unless re-throwing in a CATCH block) |
Requires preceding statement to end with semicolon (;) statement terminator? |
NO. |
YES. The statement before the THROW statement must be followed by the semicolon (;) statement terminator. |
CAN RAISE SYSTEM ERROR MESSAGE?
The SYS.MESSAGES Table will have both system-defined and user-defined messages. Message IDs less than 50000 are system messages. |
YES. With RAISERROR we can raise the System Exception.
Example:
RAISERROR (40655,16,1)RESULT:
Msg 40655, Level 16, State 1, Line 1
Database ‘master’ cannot be restored. |
NO. With THROW we can’t raise the System Exception. But when it used in CATCH BLOCK it can Re-THROW the system exception.Example: Trying to raise system exception (i.e. exception with ErrorNumber less than 50000).
THROW 40655, ‘Database master cannot be restored.’, 1
RESULT:
Msg 35100, Level 16, State 10, Line 1
Error number 40655 in the THROW statement is outside the valid range. Specify an error number in the valid range of 50000 to 2147483647 |
CAN RAISE user-defined message with message_id greater than 50000 which is not defined in SYS.MESSAGES table? |
NO. If a msg_id is passed to RAISERROR, the ID must be defined in sys.messages.Example:
RAISERROR (60000, 16, 1)
RESULT:
Msg 18054, Level 16, State 1, Line 1
Error 60000, severity 16, state 1 was raised, but no message with that error number was found in sys.messages. If error is larger than 50000, make sure the user-defined message is added using sp_addmessage.
Now add the Message to SYS.MESSAGES Table by using the below statement:
EXEC sys.sp_addmessage 60000, 16, ‘Test User Defined Message’
Now try to Raise the Error:
RAISERROR (60000, 16, 1)
RESULT:
Msg 60000, Level 16, State 1, Line 1
Test User Defined Message |
YES. The error_number parameter does not have to be defined in sys.messages.Example:
THROW 60000, ‘Test User Defined Message’, 1RESULT:
Msg 60000, Level 16, State 1, Line 1
Test User Defined Message |
Allows substitution parameters in the message parameter?
By using the below statement add a sample test message with parameteres to the SYS.Messages Table:
EXEC sp_addmessage 70000,16,‘Message with Parameter 1: %d and Parameter 2:%s’ |
YES.The msg_str parameter can contain printf formatting styles.Example 1:
RAISERROR (70000, 16, 1, 505,‘Basavaraj’ )
RESULT:
Msg 70000, Level 16, State 1, Line 1
Message with Parameter 1: 505 and Parameter 2:Basavaraj |
NO.The message parameter does not accept printf style formatting.Example 1:
THROW 70000, ‘Message with Parameter 1: %d and Parameter 2:%s’, 1, 505,’Basavaraj’
RESULT:
Msg 102, Level 15, State 1, Line 1
Incorrect syntax near ‘,’.
Alternative Way of doing this is:
DECLARE @ErrorMsg NVARCHAR(2048) = FORMATMESSAGE(70000, 505, ‘Basavaraj’ );
THROW 70000, @ErrorMsg, 1
Example 2: Message manipulation is not allowed in the THROW statement
Below statement will fail
THROW 58000,‘String1’ + ‘ String2’,1
RESULT:
Msg 102, Level 15, State 1, Line 1
Incorrect syntax near ‘+’.
We can solve such problems, we can prepare the message prior to the THROW statement and then pass it to throw statement as a variable. Below example illustrates this.
DECLARE @message NVARCHAR(2048)
SET @message = ‘String1’ + ‘ String2’;
THROW 58000, @message, 1
RESULT:
Msg 58000, Level 16, State 1, Line 3
String1 String2 |