title: how to check if two points are on the same line in postgis
body: <p>I have extracted the geometries of all intersections and I want to find all the connections (such as intersection one is connected to intersections two, three, four, five). I was thinking about achieving this by checking if two intersections (points) are on the same LineString. Does anybody know if this is a good way to do so? Is there any functions to call to check if two points are on the same line? Thank you  </p>