Given two shapes A and B, ST_Disjoint(A, B)
returns true
if the shapes do not share any of the same space -- that is, if no point in the set that comprises A is also a member of the set of points that make up B.
ST_Disjoint
works on the following spatial data types:
ST_Disjoint
does not make use of spatial indexes.
This function is the inverse of ST_Intersects
.
Examples
The screenshots in these examples were generated using geojson.io, but they are designed to showcase the shapes, not the map. Representing GEOMETRY
data in GeoJSON can lead to unexpected results if using geometries with SRIDs other than 4326 (as shown below).
True
In this example, ST_Disjoint
returns true
because:
- No Point in the set that comprises Polygon A is also a member of the set of points that make up Polygon B.
SELECT st_disjoint(st_geomfromtext('SRID=4326;POLYGON((-87.906471 43.038902, -95.992775 36.153980, -75.704722 36.076944, -87.906471 43.038902), (-87.623177 41.881832, -90.199402 38.627003, -82.446732 38.413651, -87.623177 41.881832))'), st_geomfromtext('SRID=4326;POLYGON((-87.356934 41.595161, -84.512016 39.103119, -86.529167 39.162222, -87.356934 41.595161))'));
st_disjoint
---------------
true
(1 row)
False
In this example, ST_Disjoint
returns false
because:
- Many Points in the set that comprises Polygon A are also members of the set of points that make up Polygon B.
SELECT st_disjoint(st_geomfromtext('SRID=4326;POLYGON((-87.906471 43.038902, -95.992775 36.153980, -75.704722 36.076944, -87.906471 43.038902))'), st_geomfromtext('SRID=4326;POLYGON((-84.191605 39.758949, -75.165222 39.952583, -78.878738 42.880230, -84.191605 39.758949))'));
st_disjoint
---------------
false
(1 row)
See also
- Working with Spatial Data
- Spatial and GIS Glossary of Terms
- Spatial indexes
- Spatial functions
ST_Covers
ST_CoveredBy
ST_Contains
ST_Within
ST_Intersects
ST_CoveredBy
ST_Covers
ST_Equals
ST_Overlaps
ST_Touches
ST_ConvexHull
ST_Union
- Migrate from Shapefiles
- Migrate from GeoJSON
- Migrate from GeoPackage
- Migrate from OpenStreetMap
- Introducing Distributed Spatial Data in Free, Open Source CockroachDB (blog post)