PostGIS
Name
CreateTopology — Creates a new topology schema and registers it in the topology.topology table.
Synopsis
integer +`*`+CreateTopology*(`varchar
`topology_schema_name`)`;
integer +`*`+CreateTopology*(`varchar `topology_schema_name,
integer srid`)`;
integer +`*`+CreateTopology*(`varchar `topology_schema_name,
integer srid, double precision prec`)`;
integer +`*`+CreateTopology*(`varchar `topology_schema_name,
integer srid, double precision prec, boolean hasz`)`;
Description
Creates a new topology schema with name topology_name and registers
it in the topology.topology table. Topologies must be uniquely
named. The topology tables (edge_data, face, node,and
relation are created in the schema. It returns the id of the
topology.
The srid is the
spatial reference
system SRID for the topology.
The tolerance prec is measured in the units of the spatial reference
system. The tolerance defaults to 0.
hasz defaults to false if not specified.
This is similar to the SQL/MM ST_InitTopoGeo but has more functionality.
Availability: 1.1
Enhanced: 2.0 added the signature accepting hasZ
Examples
Create a topology schema called ma_topo that stores edges and nodes
in Massachusetts State Plane-meters (SRID = 26986). The tolerance
represents 0.5 meters since the spatial reference system is meter-based.
SELECT topology.CreateTopology('ma_topo', 26986, 0.5);Create a topology for Rhode Island called ri_topo in spatial
reference system State Plane-feet (SRID = 3438)
SELECT topology.CreateTopology('ri_topo', 3438) AS topoid;
topoid
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