API Reference | OSGeo FDO Provider for SHP |
Introduction
The Feature Data Objects (FDO) API provides access to data in a data store. A provider is a specific implementation of the FDO API that provides access to data in a particular data store. The FDO Provider for SHP provides FDO with access to a SHP-based data store.
The standalone ESRI SHP file format supports GIS data using a number of separate files: SHP (shape geometry), SHX (shape index), PRJ (projection information), CPG (code page files), IDX (spatial index), and DBF (shape attributes in dBASE format). You must have either a SHP or DBF file present to connect to data or work with schemas. Otherwise, these files are optional. Files with empty records are created, if they do not exist initially.
In AutoCAD Map 3D 2008, the Schema Editor treats each SHP file, and its associated DBF file, as a feature class with a single geometry property and, optionally, data attribute properties. The SHP file format supports a single writer at any time, with multiple readers.
SHP files can include only one geometry type per file, but you can stored and copy to multiple SHP files in a folder. You can use a configuration file to support multiple schemas when you establish your connection to a folder containing SHP files.
A SHP schema can support the following:
- A single geometry type per file
- Spatial contexts (determined by coordinate system information in the PRJ file)
- Auto ID generation
- Null value constraints
- These geometry types: point, line string, polygon, multi-point, multi-line string, multi-polygon, linear ring, and line string segment.
For more information, see The Essential FDO (FET_TheEssentialFDO.pdf) and the FDO Developer's Guide (FDG_FDODevGuide.pdf).
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