CAST and CONVERTEach example retrieves the titles for those books that have a 3 in the first digit of year-to-date sales, and converts their ytd_sales to char(20).

-- Use CAST. 
USE pubs 
GO 
SELECT SUBSTRING(title, 1, 30) AS Title, 
ytd_sales FROM titles WHERE 
CAST(ytd_sales AS char(20)) LIKE '3%' 
GO  
-- Use CONVERT. 
USE pubs 
GO 
SELECT SUBSTRING(title, 1, 30) AS Title, 
ytd_sales FROM titles WHERE 
CONVERT(char(20), ytd_sales) LIKE '3%' GO 

Here is the result set (for either query):

Title                          
ytd_sales    
------------------------------ 
-----------  Cooking with Computers: 
Surrep 3876         
Computer Phobic AND Non-Phobic 375          
Emotional Security: A New Algo 3336         
Onions, Leeks, and Garlic: Coo 375           
(4 row(s) affected)