Why don't you simply concatenate into fixed-width, like this?
DROP TABLE #table_x
CREATE TABLE #table_x (Empno INT IDENTITY(3141593,31415), FirstName VARCHAR(25), LastName VARCHAR(25))
INSERT INTO #table_x (FirstName, LastName) VALUES
(('Francis'),('Bacon')),
(('Jean'),('Baptiste')),
(('Clarence'),('Birdseye')),
(('Charles'),('Babbage')),
(('John'),('Logie Baird'))
SELECT *,
Concatenated_FixedWidth = CAST(FirstName AS CHAR(25)) + CAST(LastName AS CHAR(25)) + CAST(Empno AS CHAR(25))
FROM #table_x
For fast, accurate and documented assistance in answering your questions, please read this article.
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