The SUBSTRING function returns a portion of either a character or binary string, or a text string, and takes three parameters:
This example displays the first initial and last name of each employee, for example, A Fuller:
USE Northwind
SELECT SUBSTRING(FirstName, 1, 1), LastName
FROM Employees
This example displays the second, third, and fourth characters of the string constant abcdef:
SELECT x = SUBSTRING('abcdef', 2, 3)
x
----------
bcd
(1 row(s) affected)