mysql distance between search

Question

so I have two tabels where one has a list of all postcodes with long and lat and the other has store data with long and lat.

What I need to know is how do I find all the stores that match the long and lat from a postcode within 30km

Answer 1

Use the Haversine formula (MySQL implementation) to calculate the distance between them. Return rows which have a distance of less or equal to 30.

Answer 2

Review this http://jan.ucc.nau.edu/~cvm/latlon_formula.html for formula, and put the formula on select statement and order by the distance