I am running the shortest_path function but it will not return rows of lines to follow from source id to target id. Is there a specific way to digitise my dataset? Does pgrouting understand intersections between lines? I digitised my lines one by one connecting snapping them together.

To be a bit more clear, in my db i have a gid for every line, plus a source and target id for that line (plus the other columns). Shouldn't the shortest path function take me from a random source id to a random target id?

I hope my problem is clear but let me know if further explanation is needed :)

Thanks in advance. A