MySQL SELECT AS combine two columns into one

If both columns can contain NULL, but you still want to merge them to a single string, the easiest solution is to use CONCAT_WS():

SELECT FirstName AS First_Name
     , LastName AS Last_Name
     , CONCAT_WS('', ContactPhoneAreaCode1, ContactPhoneNumber1) AS Contact_Phone 
  FROM TABLE1

This way you won't have to check for NULL-ness of each column separately.

Alternatively, if both columns are actually defined as NOT NULL, CONCAT() will be quite enough:

SELECT FirstName AS First_Name
     , LastName AS Last_Name
     , CONCAT(ContactPhoneAreaCode1, ContactPhoneNumber1) AS Contact_Phone 
  FROM TABLE1

As for COALESCE, it's a bit different beast: given the list of arguments, it returns the first that's not NULL.


You don't need to list ContactPhoneAreaCode1 and ContactPhoneNumber1

SELECT FirstName AS First_Name, 
LastName AS Last_Name, 
COALESCE(ContactPhoneAreaCode1, ContactPhoneNumber1) AS Contact_Phone 
FROM TABLE1