Sandro, Using your help, I filled most holes but three I couldn't fill using the "UPDATE ... SET topogeom ..." approach. Will explore other approaches later.
Re the presence of holes, I may have deleted faces when running my function for removing extra nodes. This needs checking. Advancing in my work, I also got to drop edge 6341 and I end up with this: https://dl.dropboxusercontent.com/u/5196336/edge6340.bmp So the next step is to split edge 6340 about its middle, with the goal of then connecting the newly created node with node 4753, thus creating an edge where there should be one (i.e. on the light grey line). However, I get the error: *point not on edge* when running ST_ModEdgeSplit. First, I tried to find the new node location using the coordinate capture tool in QGIS but because I got that error I thought maybe I really need to find a point that's on the edge so I used this approach: /WITH edge AS (SELECT geom line FROM de_20k_topo.edge_data WHERE edge_id = 6340 ), point AS (SELECT e.line, ST_ClosestPoint(e.line, ST_GeomFromText('POINT(-208737.346 811681.163)', 32198)) point FROM edge e ) SELECT ST_ModEdgeSplit('de_20k_topo', 6340, point) FROM point; / I still get the same error: point not on node. How is one supposed to find a point that IS on an edge? -- View this message in context: http://postgis.17.x6.nabble.com/Topology-cannot-delete-slivers-or-gaps-tp5007250p5007281.html Sent from the PostGIS - User mailing list archive at Nabble.com. _______________________________________________ postgis-users mailing list postgis-users@lists.osgeo.org http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users