[PostGIS] #6129: Missing area with topology.ST_GetFaceGeometry('arstat_2026_overlay_02_348',101383), but alle edges seems to be prensent

[PostGIS]

#6129: Missing area with
topology.ST_GetFaceGeometry('arstat_2026_overlay_02_348',101383), but alle
edges seems to be prensent
--------------------------------+---------------------------
  Reporter:  Lars Aksel Opsahl  |      Owner:  strk
      Type:  defect             |     Status:  new
  Priority:  medium             |  Milestone:  PostGIS 3.6.5
 Component:  topology           |    Version:  3.6.x
Resolution:                     |   Keywords:
--------------------------------+---------------------------
Comment (by strk):

 The outer ring is composed by 367 edges, connected by 367 nodes each of
 degree 2 (every connecting node has no other edge than the 2 edges forming
 the ring):

 {{{
 with node_edges as ( select start_node nod, edge_id from t6129.edge union
 all select end_node, edge_id from t6129.edge ) select nod,
 array_agg(edge_id) from node_edges where edge_id in ( select edge_id from
 t6129_outer_ring_edges  ) group by nod;
 }}}

 This is what I'd call "fully noded".

 The total number of vertices for those 367 edges is 1543, when linemerged
 we get a single line with 1177 vertices, which matches 1543-367+1:
 {{{
 strk at strk=# select sum(st_npoints(geom))-count(geom)+1 from
 t6129_outer_ring_edges;
  ?column?
 ----------
      1177
 (1 row)

 strk at strk=# select st_npoints(ST_LineMerge(ST_Collect(geom))) from
 t6129_outer_ring_edges ;
  st_npoints
 ------------
        1177
 (1 row)
 }}}

 So all seems fine.

 Where's the catch ? The LineMerge output is NOT simple !

 {{{
 strk at strk=# select ST_IsSimple(ST_LineMerge(ST_Collect(geom))) from
 t6129_outer_ring_edges ;
  st_issimple
 -------------
  f
 (1 row)
 }}}
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/6129#comment:13>
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