ST_MakeLine-ApsaraDB RDS(RDS)-阿里云帮助中心

Constructs a LineString geometry from Point, MultiPoint, or LineString geometries.

Syntax

geometry ST_MakeLine(geometry set geoms)
geometry ST_MakeLine(geometry geom1, geometry geom2)
geometry ST_MakeLine(geometry[] geomsArray)

Parameter	Description
`geoms`	The geometry objects that you want to specify.
`geom1`	The first geometry object.
`geom2`	The second geometry object.
`geomsArray`	An array of geometry objects.

Unsupported input types: Only Point, MultiPoint, and LineString geometries are accepted. Any other geometry type is silently ignored.
Common nodes: When a LineString object is added, this function deletes the common nodes at the beginning of lines. If you specify points or MultiPoints, this function does not delete the common nodes at the beginning of points or MultiPoints.
3D support: 3D geometries are fully supported. The Z coordinate of input geometries is preserved in the output.

Construct a LineString from two points.

SELECT ST_AsText(ST_MakeLine(ST_MakePoint(1,2), ST_MakePoint(3,4)));

Output:

      st_astext
---------------------
 LINESTRING(1 2,3 4)
(1 row)

Construct a LineString from an array of points.

SELECT ST_AsText(ST_MakeLine(ARRAY[ST_MakePoint(1,2), ST_MakePoint(3,4), ST_MakePoint(5,6)]));

Output:

        st_astext
-------------------------
 LINESTRING(1 2,3 4,5 6)
(1 row)

Construct a 3D LineString. The Z coordinate is preserved in the output.

SELECT ST_AsText(ST_MakeLine(ST_MakePoint(1,2,3), ST_MakePoint(4,5,6)));

Output:

         st_astext
----------------------------
 LINESTRING Z (1 2 3,4 5 6)
(1 row)