Name

AddEdge — Adds a linestring edge to the edge table and associated start and end points to the point nodes table of the specified topology schema using the specified linestring geometry and returns the edgeid of the new (or existing) edge.

Synopsis

integer AddEdge(varchar toponame, geometry aline);

Description

Adds an edge to the edge table and associated nodes to the nodes table of the specified toponame schema using the specified linestring geometry and returns the edgeid of the new or existing record. The newly added edge has "universe" face on both sides and links to itself.

[Note]

If the aline geometry crosses, overlaps, contains or is contained by an existing linestring edge, then an error is thrown and the edge is not added.

[Note]

The geometry of aline must have the same srid as defined for the topology otherwise an invalid spatial reference sys error will be thrown.

Performed by the GEOS module.

Availability: 2.0.0

Examples

SELECT topology.AddEdge('ma_topo', ST_GeomFromText('LINESTRING(227575.8 893917.2,227591.9 893900.4)', 26986) ) As edgeid;
-- result-
edgeid
--------
 1

SELECT topology.AddEdge('ma_topo', ST_GeomFromText('LINESTRING(227591.9 893900.4,227622.6 893844.2,227641.6 893816.5,
 227704.5 893778.5)', 26986) ) As edgeid;
-- result --
edgeid
--------
 2

 SELECT topology.AddEdge('ma_topo', ST_GeomFromText('LINESTRING(227591.2 893900, 227591.9 893900.4,
  227704.5 893778.5)', 26986) ) As edgeid;
 -- gives error --
 ERROR:  Edge intersects (not on endpoints) with existing edge 1

See Also

TopoGeo_AddLineString, CreateTopology, Section 4.1.3.1, “The SPATIAL_REF_SYS Table and Spatial Reference Systems”