CreateTopology
Name
CreateTopology — Creates a new topology schema and registers this new schema 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 schema with name
topology_name
consisting of tables (
edge_data
,
face
,
node
,
relation
and registers this new topology in the topology.topology table. It returns the id of the topology in the topology table. The srid is the spatial reference identified as
defined in spatial_ref_sys table for that topology. Topologies must be uniquely named. The tolerance is measured in the units of the spatial reference system. If the tolerance (
prec
) is not specified defaults to 0.
This is similar to the SQL/MM
ST_InitTopoGeo
but a bit more functional.
hasz
defaults to false if not specified.
Availability: 1.1
Enhanched: 2.0 added the signature accepting hasZ
Examples
This example creates a new schema called ma_topo that will store edges, faces, and relations in Massachusetts State Plane meters. The tolerance represents 1/2 meter since the spatial reference system is a meter based spatial reference system
SELECT topology.CreateTopology('ma_topo',26986, 0.5);
Create Rhode Island topology in State Plane ft
SELECT topology.CreateTopology('ri_topo',3438) As topoid;
topoid
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