How to find features within a distance? [duplicate]

Question

This question already has an answer here:

• How do I use st_dwithin with meters? 2 answers

I insert the values from lat/long into the points. Those users move around and send me new Lat/long and of course , I made an update of the position.

I need to find people that are in a distance less than 100Km, which is the best approach to do that?.

Answer 1

You could use St_DWithin

http://postgis.refractions.net/docs/ST_DWithin.html

This will enable you to find points within a set distance

I believe this is what you are after as an example from the PostGIS manual

SELECT * FROM geotable WHERE ST_DWithin(geocolumn, 'POINT(1000 1000)', 100.0);