I am having some issues when using pgrouting's shortest path. I am following this tutorial available at http://workshop.pgrouting.org/chapters/shortest_path.html#dijkstra. This query returns a list of edges. Then I get the start and end points of each edge. Then I just join these points to show the shortest path. Just to let you know that I don't necessarily get the ending point of the first edge in the list to be the starting point of the second edge in the list returned. So I join, the ending and starting points of the two edges as well. However, sometimes the points are repeated and I have lines crossing over each other and the path looks a mess. What could be the reason behind this?
The result of shortest path is not ordered. Therefore you cannot rely on it. To visualize the results, you could use the edge geometries instead.