Using the SUBSTRING() SQL Server Function

Using SUBSTRING() in the SELECT clause

The SUBSTRING() function is used to extract a character string from a given starting position for a given length. 

SELECT  TOP 100
 SUBSTRING(course_designater,6,3) as 'Course number'                   
FROM    Courses
WHERE   course_designater LIKE 'Excel%'    

Format a column using SUBSTRING() and LOWER() and UPPER() functions

It is possible to use the SQL Server LOWER() and UPPER() functions in conjunction with the SUBSTRING() function to accomplish different types of formatting.

SELECT TOP 10
  UPPER(SUBSTRING (lastname,1,1)) + LOWER(SUBSTRING(lastname,2,29)) 
  AS 'Lastname'
FROM Students