The file format is the native spatial data storage format for Autodesk GIS programs MapGuide and AutoCAD Map 3D.
As of 2014[update] SDF format version SDF3 (based on SQLite3) uses a single file.
[3][4][5][6] The SDF format design uses low-level storage components of SQLite using a flat binary serialization (binary large objects).
However, the relational aspects are not present, thus the format cannot be opened with any software designed specifically for SQLite.
It is optimized for fast spatial reading of large datasets in scenarios involving a single writer and multiple readers.