Calculate Nearest Site Latitude and Longitude

Question

We have telecom Sites (Towers). Each Tower is identified by its Latitude and Longitude. We have Latitude and Longitude information in the database Site table. Suppose when we installed a new tower in a new location so how to find the nearest Site Latitude and Langitude from the New Site. Suppose conside the following method:

 

public void NearestSiteLatLong(double NewLocationLatitude, double NeLocationLongitude)

{

Fitch the stored Latitude and Langitude values from the database table Site and then compare each retrieved Latitude and Langitude from the database Table Site with the NewLocationLatitude and NewLocationLongitude and then find the nearest Latitude and Longitude 

 

} 

 

Here i am not sure how to compare i means which type of comparison is this?

 

Thanks in advance