Comparison with Oracle Spatial Geometries
Oracle Spatial, often referred to as Spatial, provides a SQL schema and functions that facilitate the storage, retrieval, update, and query of collections of spatial features in an Oracle database.1 Among other things, it enhances the database with the capability to store, retrieve and manipulate geometry data types.
Typically, a row of a table that includes a column with an Oracle Spatial geometry can be compared to a geospatial feature known to most geospatial end-user systems, including the XFM feature model.
This a comparison of the XFM Feature and Oracle Spatial geometry types:
| XFM Feature Geometry Type | Oracle Spatial Geometry Type | SDO_GTYPE | Remarks |
|---|---|---|---|
| point-cell | POINT | d/01 | A XFM point-cell with the default cell is a valid representation of an Oracle Spatial POINT. |
| collection-point-cell | MULTIPOINT | d/05 | - |
| point-text | - | - | Up to Oracle 10_g_ annotations are cartographic text are not supported. |
| collection-point-text | - | - | See previous remark. |
| linestring/curve | LINE or CURVE | d/02 | Fully compatible, can be used to represent Oracle Spatial line string, arc line string, and compound line string geometries on a XFM client. |
| collection-linestring/curve | MULTILINE or MULTICURVE | - | - |
| NURBS | d/2006 | 2D only with projected coordinate system. Supports a curve with one NURBS curve element and no other elements - no support at this time for compound line string containing NURBS curve elements. | |
| polygon | POLYGON | d/03 | Fully compatible. Can be used to represent Oracle Spatial polygon, arc polygon, compound polygon, circle, and rectangle geometries on a XFM client. |
| collection-polygon | MULTIPOLYGON | d/07 | - |
| - | UNKNOWN_GEOMETRY | d/00 | XFM does not support features of type unknown. |
| - | COLLECTION | d/04 | XFM does not support heterogeneous collections of elements for one single feature. Note that heterogeneous collections of elements can be constructed by defining hierarchies of features and sub-features. |
The _d_ in the SDO_GTYPE column stands for the number of dimensions. Up to release 10g, Oracle Spatial's functionality (for example, spatial operators) is limited to two dimensions, but the storage of 3 or even 4 dimensional geometry values is supported.
Oracle Spatial Documentation for Oracle Spatial 10_g_ Release 2