Nested String Functions

String functions can be nested. For example, to display the last name and the first initial of each author living in Oakland, with a comma after the last name and a period after the first initial:

SELECT (au_lname  ',' + '' + substring(au_fname, 1, 1) + '.')
FROM authors
WHERE city = 'Oakland'

----------------------
Green, M.
Straight, D.
Stringer, D.
MacFeather, S.
Karsen, L.

(5 row(s) affected)

To display the pub_id and the first two characters of each title_id for books over $20:

SELECT substring(pub_id  title_id, 1, 6)
FROM titles
WHERE price > $20

For details about other string functions, see Functions in the Microsoft SQL Server Transact-SQL Reference.