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# Weather Observation Station 4

[Question Link](https://www.hackerrank.com/challenges/weather-observation-station-4/problem?isFullScreen=true)

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: \
![](https://s3.amazonaws.com/hr-challenge-images/9336/1449345840-5f0a551030-Station.jpg)

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 returns 1, because total number of records - number of unique city names = 3 - 2 = 1

```sql
SELECT COUNT(city) - COUNT(DISTINCT city)
FROM Station;
```


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