POINT

A POINT is a sizeless location identified by its X and Y coordinates. These coordinates are then translated according to the current spatial reference system (denoted by an SRID) to determine what the Point “is”, or what it “means” relative to the other spatial objects (if any) in the data set. You can also store a POINT with the following additional dimensions:

A third dimension coordinate Z ( POINTZ ).
A measure coordinate M ( POINTM ).
Both a third dimension and a measure coordinate ( POINTZM ).

The Z and M dimensions can be accessed or modified using a number of built-in functions, including:

ST_Z
ST_M
ST_Affine
ST_Zmflag
ST_MakePoint
ST_MakePointM
ST_Force3D
ST_Force3DZ
ST_Force3DM
ST_Force4D
ST_Snap
ST_SnapToGrid
ST_RotateZ
ST_AddMeasure

Note that CockroachDB’s spatial indexing is still based on the 2D coordinate system. This means that:

The Z/M dimension is not index accelerated when using spatial predicates.
Some spatial functions ignore the Z/M dimension, with transformations discarding the Z/M value.

Examples

SQL

A Point can be created in SQL by the st_point function. The statement below creates a Point (using the common SRID 4326).

SELECT ST_SetSRID(ST_Makepoint(0,0), 4326);

                      st_setsrid
------------------------------------------------------
  0101000020E610000000000000000000000000000000000000
(1 row)

Well known text

A Point can be created from SQL by calling the st_geomfromtext function on a Point definition expressed in the Well Known Text (WKT) format as shown below.

SELECT ST_GeomFromText('POINT(0 0)');

               st_geomfromtext
----------------------------------------------
  010100000000000000000000000000000000000000
(1 row)

Statements

Syntax

Data Types

Spatial Data

Constraints

Examples

SQL

Well known text

See also

​Examples

​SQL

​Well known text

​See also

Examples

SQL

Well known text

See also