ST_AsShape function

The St_AsShape function takes a geometry as an input parameter and returns its ESRI shape format.

If the specified geometry is null, then null is returned.

Syntax

Parameter

geometry: A value of type ST_Geometry or one of its subtypes to be converted to the corresponding ESRI shape format.

Return type

BLOB(2G)

Example

The following code fragment illustrates how to use the ST_AsShape function to convert the points in the geometry column of the SAMPLE_POINTS table into shape binary representation in the shape column. This example populates the shape column from the geometry column. The shape binary representation is used to display the geometries in geobrowsers, which require geometries to comply with the ESRI shapefile format, or to construct the geometries for the *.SHP file of the shape file.



CREATE TABLE SAMPLE_POINTS (id integer, geometry ST_POINT, shape varbinary(32000))
;
INSERT INTO SAMPLE_POINTS (id, geometry)
VALUES
    (1100, ST_Point(10, 20, 1))
;
INSERT INTO sample_points(id, shape)
VALUES (2222,
  (SELECT  ST_AsShape(geometry)
   FROM    sample_points
   WHERE   id = 1100))
;

UPDATE sample_points SET geometry = st_point(shape, 1) WHERE id = 2222
;

SELECT id, substr(ST_AsShape(geometry), 1, 20) AS shape
FROM   sample_points
;

Returns:


ID     SHAPE

----------- -------------------------------------------
       1100 x'0100000000000000000024400000000000003440'
       2222 x'0100000000000000000024400000000000003440'


SELECT id, substr(ST_AsText(geometry), 1, 50) AS shape FROM sample_points
;

Returns:


ID          SHAPE
----------- --------------------------------------------------
       1100 POINT (10.000000 20.000000)
       2222 POINT (10.000000 20.000000)