The Spatial Data File (SDF) is a single-user geodatabase

file format A file format is a Computer standard, standard way that information is encoded for storage in a computer file. It specifies how bits are used to encode information in a digital storage medium. File formats may be either proprietary format, pr ...

developed by

Autodesk Autodesk, Inc. is an American multinational software corporation that provides software products and services for the architecture, engineering, construction, manufacturing, media, education, and entertainment industries. Autodesk is headquarte ...

. The file format is the native spatial data storage format for Autodesk GIS programs MapGuide and AutoCAD Map 3D. SDF format version SDF3 (based on

SQLite3 SQLite ( "S-Q-L-ite", "sequel-ite") is a free and open-source relational database engine written in the C programming language. It is not a standalone app; rather, it is a library that software developers embed in their apps. As such, it ...

) uses a single file. Prior versions of the format required a ''spatial index file'' (SIF), with an optional ''key index file'' (KIF) to speed access to the file. The SDF file format can be created and manipulated using an OSGeo FDO Provider for SDF, which is

open-source software Open-source software (OSS) is Software, computer software that is released under a Open-source license, license in which the copyright holder grants users the rights to use, study, change, and Software distribution, distribute the software an ...

. Beyond Autodesk's products, products that can read/write the format include FME from Safe Software, Fdo2Fdo, and the FdoToolbox. The SDF format design uses low-level storage components of

SQLite SQLite ( "S-Q-L-ite", "sequel-ite") is a free and open-source relational database engine written in the C programming language. It is not a standalone app; rather, it is a library that software developers embed in their apps. As such, it ...

using a flat binary serialization (

binary large object Object storage (also known as object-based storage or blob storage) is a computer data storage approach that manages data as "blobs" or "objects", as opposed to other storage architectures like file systems, which manage data as a file hierarchy, ...

s). However, the relational aspects are not present, thus the format cannot be opened with any software designed specifically for SQLite. The format supports multiple feature classes per file and multiple geometry properties per feature class. Each geometry property is indexed using an

R-tree R-trees are tree data structures used for spatial access methods, i.e., for indexing multi-dimensional information such as geographical coordinates, rectangles or polygons. The R-tree was proposed by Antonin Guttman in 1984 and has found s ...

. It is optimized for fast spatial reading of large datasets in scenarios involving a single writer and multiple readers.

References

{{Reflist

External links

SDF Loader
provided by Autodesk to convert from

Shapefile The shapefile format is a geospatial vector data format for geographic information system (GIS) software. It is developed and regulated by Esri as a mostly open specification for data interoperability among Esri and other GIS software product ...

s and other formats
Spatial Manager DesktopSpatial Manager for AutoCAD
an
Spatial Manager for BricsCAD
can read and write SDF files and other formats Autodesk GIS file formats