Chapter 2: Transact-SQL Functions

len

Returns the number of characters, not the number of bytes, of a specified string expression, excluding trailing blanks.

len(string_expression)

Returns the characters

select len(notes) from titles
where title_id = "PC9999"
-----------
39

This function is the equivalent of char_length(string_expression).

ANSI SQL – Compliance level: Transact-SQL extension.

Any user can execute len.