ST_ClusterIntersecting — 聚合函数,用于将输入几何图形聚集到相连的集合中。
geometry[]
ST_ClusterIntersecting
(
geometry set
g
)
;
ST_ClusterIntersecting是一个聚合函数,它返回GeometryCollection数组,其中每个GeometryCollection表示一组相互连接的几何图形。
可用性:2.2.0
WITH testdata AS
(SELECT unnest(ARRAY['LINESTRING (0 0, 1 1)'::geometry,
'LINESTRING (5 5, 4 4)'::geometry,
'LINESTRING (6 6, 7 7)'::geometry,
'LINESTRING (0 0, -1 -1)'::geometry,
'POLYGON ((0 0, 4 0, 4 4, 0 4, 0 0))'::geometry]) AS geom)
SELECT ST_AsText(unnest(ST_ClusterIntersecting(geom))) FROM testdata;
--result
st_astext
---------
GEOMETRYCOLLECTION(LINESTRING(0 0,1 1),LINESTRING(5 5,4 4),LINESTRING(0 0,-1 -1),POLYGON((0 0,4 0,4 4,0 4,0 0)))
GEOMETRYCOLLECTION(LINESTRING(6 6,7 7))