GeometryType — 以文本形式返回几何图形的类型。
text GeometryType(
geometry geomA)
;
以字符串形式返回几何图形的类型。例如:“LINESTRING”、“POLYGON”、“MULTPOINT”等。
OGC规范s2.1.1.1-返回该Geometry实例所属的Geometry的可实例化的子类型的名称。几何图形的可实例化的子类型的名称以字符串形式返回。
此函数还通过返回形式为‘POINTM’的字符串来指示是否测量几何图形。 |
增强:2.0.0引入了对多面体曲面、三角形和三角网的支持。
This method implements the OGC Simple Features Implementation Specification for SQL 1.1.
This method supports Circular Strings and Curves
This function supports 3d and will not drop the z-index.
This function supports Polyhedral surfaces.
This function supports Triangles and Triangulated Irregular Network Surfaces (TIN).
SELECT GeometryType(ST_GeomFromText('LINESTRING(77.29 29.07,77.42 29.26,77.27 29.31,77.29 29.07)')); geometrytype -------------- LINESTRING
SELECT ST_GeometryType(ST_GeomFromEWKT('POLYHEDRALSURFACE( ((0 0 0, 0 0 1, 0 1 1, 0 1 0, 0 0 0)), ((0 0 0, 0 1 0, 1 1 0, 1 0 0, 0 0 0)), ((0 0 0, 1 0 0, 1 0 1, 0 0 1, 0 0 0)), ((1 1 0, 1 1 1, 1 0 1, 1 0 0, 1 1 0)), ((0 1 0, 0 1 1, 1 1 1, 1 1 0, 0 1 0)), ((0 0 1, 1 0 1, 1 1 1, 0 1 1, 0 0 1)) )')); --result POLYHEDRALSURFACE
SELECT GeometryType(geom) as result FROM (SELECT ST_GeomFromEWKT('TIN ((( 0 0 0, 0 0 1, 0 1 0, 0 0 0 )), (( 0 0 0, 0 1 0, 1 1 0, 0 0 0 )) )') AS geom ) AS g; result -------- TIN