Calculate radius from coordinates and find all matches within the radius in a table

Question

Possible Duplicate:
SQL: Determine if one coordinate is in radius of another

In a table I have stored latitude and longitude (as floats). Now I want to query my table to find all rows which have coordinates within a given radius (which can ben 2km, 5km, 10km etc. etc.). I really don't have a clue how to achieve this so any help will be greatly appreciated. I'm not sure how query, because I think the result will be an endless set of coordinates representing the 'border' of the radius where I somehow have to tell my table to search for results within that 'border'.

Solution

You need to familiarize yourself with the Haversine forumla This will calculate the distances from lat and lon as you expected through mysql

Comments

[Ben Fransen]

Thanks for your answer, +1. I'm going to try Shubhansh solution first, if that won't work I'll give your suggestion a try.