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Coordinator DB
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Geometry types ​

Geometry types are named aliases over typed tuples and arrays. They preserve the shape and numeric types of coordinate collections.

Supported types ​

Type Structure
Point Tuple(Float64, Float64) — two coordinates.
MultiPoint Array(Point) — independent points.
Ring Array(Point) — a polygon boundary.
LineString Array(Point) — an ordered path.
MultiLineString Array(LineString) — a collection of paths.
Polygon Array(Ring) — an outer boundary followed by holes.
MultiPolygon Array(Polygon) — a collection of polygons.

The types validate the collection shape and coordinate conversions. They do not validate topology, such as self-intersections or whether holes lie inside an outer ring.

Use consistent coordinate units for a calculation. The aliases do not assign a coordinate reference system or convert between geographic and projected coordinates.

Examples ​

A point ​

sql
SELECT CAST('[1,2]' AS Point)
FORMAT csv;
text
"[1,2]"

Testing polygon membership ​

point_in_polygon includes the outer boundary and excludes hole boundaries:

sql
SELECT point_in_polygon(
    tuple(1, 1),
    CAST('[[0,0],[2,0],[2,2],[0,2]]' AS Ring)
)
FORMAT csv;
text
true

Storing a polygon ​

sql
CREATE TABLE regions(name String, boundary Polygon);
INSERT INTO regions VALUES
    ('square', '[[[0,0],[2,0],[2,2],[0,2]]]');
sql
SELECT name, point_in_polygon(tuple(1, 1), boundary)
FROM regions
FORMAT csv;
text
"square",true

See geometry functions and GeoJSON for geometry operations and interchange.