Spatial objects

Vertica implements several data types for storing spatial objects, Well-Known Text (WKT) strings, and Well-Known Binary (WKB) representations.

1: Supported spatial objects
2: Spatial reference identifiers (SRIDs)

Vertica implements several data types for storing spatial objects, Well-Known Text (WKT) strings, and Well-Known Binary (WKB) representations. These data types include:

1 - Supported spatial objects

Vertica supports two spatial data types. These data types store two- and three-dimensional spatial objects in a table column:

GEOMETRY: Spatial object with coordinates expressed as (x,y) pairs, defined in the Cartesian plane. All calculations use Cartesian coordinates.
GEOGRAPHY: Spatial object defined as on the surface of a perfect sphere, or a spatial object in the WGS84 coordinate system. Coordinates are expressed in longitude/latitude angular values, measured in degrees. All calculations are in meters. For perfect sphere calculations, the sphere has a radius of 6371 kilometers, which approximates the shape of the earth.

Note
Some spatial programs use an ellipsoid to model the earth, resulting in slightly different data.

The maximum size of a GEOMETRY or GEOGRAPHY data type is 10,000,000 bytes (10 MB). You cannot use either data type as a table's primary key.

2 - Spatial reference identifiers (SRIDs)

A spatial reference identifier (SRID) is an integer value that represents a method for projecting coordinates on the plane.

A spatial reference identifier (SRID) is an integer value that represents a method for projecting coordinates on the plane. A SRID is metadata that indicates the coordinate system in which a spatial object is defined.

Geospatial functions using Geometry arguments must contain the same SRID. If the functions do not contain the same SRID, then the query returns an error.

For example, in this query the two points have different SRIDs. As a result the query returns an error:

=> SELECT ST_Distance(ST_GeomFromText('POINT(34 9)',2749), ST_GeomFromText('POINT(70 12)', 3359));
ERROR 5861:  Error calling processBlock() in User Function ST_Distance at [src/Distance.cpp:65],
error code: 0, message: Geometries with different SRIDs found: 2749, 3359

Supported SRIDs

Vertica supports SRIDs derived from the EPSG standards. Geospatial functions using Geometry arguments must use supported SRIDs when performing calculations. SRID values of 0 to 2^32-1 are valid. Queries with SRID values outside of this range will return an error.