Problem using pgr_createTopology

Question

When I run select pgr_createTopology('public.roads', 0.0001, 'geom', 'id');, all I get is "FAIL". The roads table has these fields:

id (integer)
source (integer)
target (integer)
geom (geometry LineStringM,3006)

What am I missing? I have been unable to find a list of requirements for the network table, which I create using FME. I use pgRouting 2.2.2.

Answer 1

The geometrytype should be LineString, not LineStringM.

Try changing your geom column to LineString with this:

ALTER TABLE public.roads 
  ALTER COLUMN geom TYPE geometry(LineString,3006)
  USING ST_Force2D(geom);

Answer 2

Debes tener errores topológicos, verifica que no tengas líneas duplicadas, arcos, etc.. debes tener una capa super limpia topológicamente hablando.

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English translation:

You must have topological errors, verify that you do not have duplicate lines, arcs, etc. You must have a super clean layer topologically speaking.