RAISERROR (Transact-SQL)
Generates an error message and initiates error processing for the session. RAISERROR can either reference a user-defined message stored in the sys.messages catalog view or build a message dynamically. The message is returned as a server error message to the calling application or to an associated CATCH block of a TRY…CATCH construct.
The errors generated by RAISERROR operate the same as errors generated by the Database Engine code. The values specified by RAISERROR are reported by the ERROR_LINE, ERROR_MESSAGE, ERROR_NUMBER, ERROR_PROCEDURE, ERROR_SEVERITY, ERROR_STATE, and @@ERROR system functions. When RAISERROR is run with a severity of 11 or higher in a TRY block, it transfers control to the associated CATCH block. The error is returned to the caller if RAISERROR is run:
Outside the scope of any TRY block.
With a severity of 10 or lower in a TRY block.
With a severity of 20 or higher that terminates the database connection.
CATCH blocks can use RAISERROR to rethrow the error that invoked the CATCH block by using system functions such as ERROR_NUMBER and ERROR_MESSAGE to retrieve the original error information. @@ERROR is set to 0 by default for messages with a severity from 1 through 10. For more information, see Using TRY...CATCH in Transact-SQL.
When msg_id specifies a user-defined message available from the sys.messages catalog view, RAISERROR processes the message from the text column using the same rules as are applied to the text of a user-defined message specified using msg_str. The user-defined message text can contain conversion specifications, and RAISERROR will map argument values into the conversion specifications. Use sp_addmessage to add user-defined error messages and sp_dropmessage to delete user-defined error messages.
RAISERROR can be used as an alternative to PRINT to return messages to calling applications. RAISERROR supports character substitution similar to the functionality of the printf function in the C standard library, while the Transact-SQL PRINT statement does not. The PRINT statement is not affected by TRY blocks, while a RAISERROR run with a severity of 11 to 19 in a TRY block transfers control to the associated CATCH block. Specify a severity of 10 or lower to use RAISERROR to return a message from a TRY block without invoking the CATCH block.
Typically, successive arguments replace successive conversion specifications; the first argument replaces the first conversion specification, the second argument replaces the second conversion specification, and so on. For example, in the following RAISERROR statement, the first argument of N'number' replaces the first conversion specification of %s; and the second argument of 5 replaces the second conversion specification of %d.
RAISERROR (N'This is message %s %d.', -- Message text. 10, -- Severity, 1, -- State, N'number', -- First argument. 5); -- Second argument. -- The message text returned is: This is message number 5. GO
If an asterisk (*) is specified for either the width or precision of a conversion specification, the value to be used for the width or precision is specified as an integer argument value. In this case, one conversion specification can use up to three arguments, one each for the width, precision, and substitution value.
For example, both of the following RAISERROR statements return the same string. One specifies the width and precision values in the argument list; the other specifies them in the conversion specification.
RAISERROR (N'<<%*.*s>>', -- Message text. 10, -- Severity, 1, -- State, 7, -- First argument used for width. 3, -- Second argument used for precision. N'abcde'); -- Third argument supplies the string. -- The message text returned is: << abc>>. GO RAISERROR (N'<<%7.3s>>', -- Message text. 10, -- Severity, 1, -- State, N'abcde'); -- First argument supplies the string. -- The message text returned is: << abc>>. GO
A. Returning error information from a CATCH block
The following code example shows how to use RAISERROR inside a TRY block to cause execution to jump to the associated CATCH block. It also shows how to use RAISERROR to return information about the error that invoked the CATCH block.
Note |
|---|
RAISERROR only generates errors with state from 1 through 127. Because the Database Engine may raise errors with state 0, we recommend that you check the error state returned by ERROR_STATE before passing it as a value to the state parameter of 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;
B. Creating an ad hoc message in sys.messages
The following example shows how to raise a message stored in the sys.messages catalog view. The message was added to the sys.messages catalog view by using the sp_addmessage system stored procedure as message number 50005.
sp_addmessage @msgnum = 50005, @severity = 10, @msgtext = N'<<%7.3s>>'; GO RAISERROR (50005, -- Message id. 10, -- Severity, 1, -- State, N'abcde'); -- First argument supplies the string. -- The message text returned is: << abc>>. GO sp_dropmessage @msgnum = 50005; GO
C. Using a local variable to supply the message text
The following code example shows how to use a local variable to supply the message text for a RAISERROR statement.
DECLARE @StringVariable NVARCHAR(50);
SET @StringVariable = N'<<%7.3s>>';
RAISERROR (@StringVariable, -- Message text.
10, -- Severity,
1, -- State,
N'abcde'); -- First argument supplies the string.
-- The message text returned is: << abc>>.
GO
