Custom RAISERROR in SQL Server 2005 (T-SQL)

how to add custom message %s is place holder for argument:

 exec sp_addmessage @msgnum = 60555, @severity = 16,
@msgtext = 'MSIEX:[[%s]]',
@lang = 'us_english';
go

to see your message in messages table:

SELECT * FROM sys.messages

Assert procedure in TSQL :

ALTER  PROC      usl_AssertionsThrow
@msg VARCHAR(MAX)
AS
BEGIN
         RAISERROR ( 60555, 20, 1,@msg) WITH LOG
END

this setting terminate stored procedure after RAISERROR

SET XACT_ABORT ON

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