[MySQL/HackerRank] Weather Observation Station 4

Find the difference between the total number of CITY entries in the table and the number of distinct CITY entries in the table.
The STATION table is described as follows:

where LAT_N is the northern latitude and LONG_W is the western longitude.

For example, if there are three records in the table with CITY values 'New York', 'New York', 'Bengalaru', there are 2 different city names: 'New York' and 'Bengalaru'.

The query retruns 1, because Total number of records - number of unique city names = 3 - 2 = 1 

SELECT
    COUNT(CITY) - COUNT(DISTINCT CITY)
FROM
	STATION
WHERE
	LAT_N >0 AND LONG_W >0

 

HackerRank MySQL EASY