Polygon Constructors - Ocient Documentation

POLYGON constructors use geospatial data to create a POLYGON object.

ST_FORCECCW

Creates a standardized polygon from an existing one. defines standardized as the exterior being counterclockwise (CCW) and all holes being clockwise (CW) oriented. Syntax

SQL

ST_FORCECCW(polygon)

Argument	Data Type	Description
`polygon`	`POLYGON`	A `POLYGON` to be converted on its exterior counterclockwise and clockwise for any interior holes.

Example

SQL

SELECT ST_FORCECCW(ST_POLYGON('POLYGON((0 0,0 1,1 1,1 0,0 0))'));

Output: POLYGON((0 0,1 0,1 1,0 1,0 0))

ST_MAKEPOLYGON

Alias for ST_POLYGON.

ST_POLYGON

Creates a POLYGON.

ST_POLYGON(geo)

Creates a POLYGON from the specified POINT, POINT array, LINESTRING, or POLYGON geography. Syntax

SQL

ST_POLYGON(geo)

Argument	Data Type	Description
`geo`	`POLYGON`	A `POINT`, `POINT` array, `LINESTRING`, or `POLYGON` value to be converted to a `POLYGON` object.

Example

SQL

SELECT ST_POLYGON(
        ST_LINESTRING(
            ST_POINT [](
                ST_POINT(1, 2),
                ST_POINT(1, 3),
                ST_POINT(1, 4),
                ST_POINT(1, 2))));

Output: POLYGON((1 2,1 3,1 4,1 2))

ST_POLYGON(char) [#st_polygon-char]

Alias for ST_MAKEPOLYGON(char). Creates a POLYGON from the specified CHAR representing a POLYGON in WKT format. Syntax

SQL

ST_POLYGON(char)

Argument	Data Type	Description
`char`	`CHAR` that represents a `POLYGON` in WKT format.	The `CHAR` argument must represent a `POLYGON` in WKT format.

Example

SQL

SELECT ST_POLYGON('POLYGON((1 2,1 3,1 4,1 2))');

Output: POLYGON((1 2,1 3,1 4,1 2))

ST_POLYGON(binary) [#st_polygon-binary]

Alias for ST_POLYGONFROMWKB(binary). Creates a POLYGON from the specified BINARY. The BINARY value must represent a POLYGON in WKB format. Syntax

SQL

ST_POLYGON(binary)

Argument	Data Type	Description
`binary`	`BINARY` that represents a `POLYGON` in WKB format.	A `BINARY` argument to be converted to a `POLYGON`. The `BINARY` value must represent a `POLYGON` in WKB format.

Example

SQL

SELECT ST_POLYGON(BINARY('0x01030000000100000005000000000000000000000000000000000000000000000000000000000000000000f03f000000000000f03f000000000000f03f000000000000f03f000000000000000000000000000000000000000000000000'));

Output: POLYGON((0 0,0 1,1 1,1 0,0 0))

ST_POLYGON(outer_ring, inner_rings)

Alias for ST_MAKEPOLYGON(outerRing, innerRings). Creates a POLYGON from the specified outer ring (that must be either a POINT, POINT array, or LINESTRING) and the array of interior rings (closed lines). The interior of the POLYGON is on the left when traveling around the exterior ring. The interior of a hole is on the right when traveling around a hole. Syntax

SQL

ST_POLYGON(outer_ring, inner_rings)

Argument	Data Type	Description
`outer_ring`	`POINT`, `POINT` array, or `LINESTRING`	A `POINT`, `POINT` array, or `LINESTRING` that represents the outer ring of the `POLYGON` object.
`inner_rings`	`ARRAY` of `POINT` arrays, or `ARRAY` of `LINESTRING` values	An `ARRAY` of `POINT` arrays or `LINESTRING` values that represents the inner rings or holes in the `POLYGON` object.

Example

SQL

SELECT ST_POLYGON(
        ST_LINESTRING(ST_POINT [](ST_POINT(1, 2))),
        ST_LINESTRING [](ST_LINESTRING(ST_POINT [](ST_POINT(1, 2)))));

Output: POLYGON((1.000000 2.000000), (1.000000 2.000000))

ST_POLYGONFROMWKB

Alias for ST_POLYGON(binary).

ST_POLYGONFROMEWKT

Alias for the ST_POLYGON constructor. Creates a POLYGON using an EWKT-formatted CHAR as an input argument. Syntax

SQL

ST_POLYGONFROMEWKT(char)

Argument	Data Type	Description
`char`	`CHAR`	A string that includes an SRID value and an EWKT-formatted value that represents a `POLYGON`. Separate the values in the string by a semicolon in this format: `'SRID = value; polygon_value'` The input string must include the `SRID = value;` component. However, the database ignores this component as all Ocient geography types are `SRID = 4326`.

Example

SQL

SELECT ST_POLYGONFROMEWKT('SRID=4326;POLYGON((1 2,1 3,1 4,1 2))');

Output: POLYGON((1 2,1 3,1 4,1 2))

ST_POLYGONFROMGEOJSON

Creates a POLYGON represented by the specified GeoJSON value as an input argument. Syntax

SQL

ST_POLYGONFROMGEOJSON(geojson [, geodesic ] )

Argument	Data Type	Description
`geo_json`	`STRING`	A string of a GeoJSON. Valid GeoJSON formats follow standards, which you can generate using the ST_ASGEOJSON function. If you specify an invalid GeoJSON, the behavior of the function is undefined. The function returns NULL if any argument is a NULL value.
`geodesic`	`BOOLEAN`	Optional. If you specify `geodesic` as `TRUE`, the function adds points to the resulting `POLYGON` such that it remains within 10 meters of the original planar polygon. If you do not specify this argument, the value defaults to `FALSE`.

Examples In this example, the function produces an empty POLYGON value from the GeoJSON representation.

SQL

SELECT ST_POLYGONFROMGEOJSON('{"type":"Polygon","coordinates":[]}',false);

Output: POLYGON EMPTY In this example, the function produces a POLYGON value from the GeoJSON representation.

SQL

SELECT ST_POLYGONFROMGEOJSON(
        '{"type":"Polygon","coordinates":[[[1,1],[1,5],[5,5],[5,1]]]}',
        false);

Output: POLYGON((1 1, 1 5, 5 5, 5 1))

ST_POLYGONFROMTEXT

Alias for ST_POLYGON(char).

ST_WHOLEEARTH

Returns the database internal representation of the whole earth polygon. The ST_ENVELOPE function returns this POLYGON value, with the envelope set as the entire earth. GIS specifications do not describe a canonical polygon for the whole earth, but this value serves as the Ocient-canonical polygon. The whole earth polygon is also equivalent to ST_POLYGON('POLYGON((0 0,0 0,0 0,0 0'))), which can have a separate meaning in other GIS implementations. Syntax

SQL

ST_WHOLEEARTH()

Example

SQL

SELECT ST_WHOLEEARTH();

Output: POLYGON((0.0 0.0, 0.0 0.0, 0.0 0.0, 0.0 0.0)) Geospatial Data Types Conversion Functions

​ST_FORCECCW

​ST_MAKEPOLYGON

​ST_POLYGON

​ST_POLYGON(geo)

​ST_POLYGON(char) [#st_polygon-char]

​ST_POLYGON(binary) [#st_polygon-binary]

​ST_POLYGON(outer_ring, inner_rings)

​ST_POLYGONFROMWKB

​ST_POLYGONFROMEWKT

​ST_POLYGONFROMGEOJSON

​ST_POLYGONFROMTEXT

​ST_WHOLEEARTH

​Related Links

ST_FORCECCW

ST_MAKEPOLYGON

ST_POLYGON

ST_POLYGON(geo)

ST_POLYGON(char) [#st_polygon-char]

ST_POLYGON(binary) [#st_polygon-binary]

ST_POLYGON(outer_ring, inner_rings)

ST_POLYGONFROMWKB

ST_POLYGONFROMEWKT

ST_POLYGONFROMGEOJSON

ST_POLYGONFROMTEXT

ST_WHOLEEARTH

Related Links