MySQL query with DISTINCT keyword

Question

My MySQL table country_phone_codes looks something like this

id     country_code     area_code     name
---------------------------------------------------------         


        

Answer 1

As you seem to want to select those rows, where the area_code is the same as country_code, you could just select those rows where area_code and country_code are equal:

SELECT country_code, name
FROM country_phone_codes
WHERE area_code = country_code;

If there is possibility that there are multiple rows with the same area code and country code, you can use DISTINCT to select only one row for each (country_code, name) tuple.

SELECT DISTINCT country_code, name
FROM country_phone_codes
WHERE area_code = country_code;