st_length
How PostGIS runs Measure Length: st_length.
| Engine | PostGIS |
|---|---|
| Tool name | st_length |
| Interface | sql |
| Implements | Measure Length |
| Documentation | Not stated |
| Effects | modifies input: no, network: no |
| Notes | Not stated |
| Status | active |
Parameters
| Name | Type | Required | Default | Choices | Note |
|---|---|---|---|---|---|
geog | geography | no | Not stated | Not stated | Not stated |
use_spheroid | boolean | no | true | Not stated | Not stated |
SQL overloads
-
st_length(geog geography, use_spheroid boolean DEFAULT true) → double precision -
st_length(geometry) → double precision -
st_length(text) → double precision
How it maps to the operation
| Operation parameter | Parameter here | Note |
|---|---|---|
layer | #1 | Not stated |
unit | Not stated | always crs-units. CRS units (metres in a metric CRS); convert afterwards for other units. |
Differences from the operation
- Returns 0 for polygons (ST_Perimeter measures outlines); on geography, metres on the spheroid.
Harvested by the postgis harvester from engine version
3.7.0. Names can change when an engine is harvested again.