ArcSDE compressed binary storage

The ArcSDE Compressed Binary storage type uses a binary storage mechanism for storing feature geometry.

The client application, after verifying the geometry, compresses and sends it to the server, where it is stored in Compressed Binary format in a feature table, or F table. Compressing the geometry on the client unloads the task from the ArcSDE server and reduces the transmission time to send the geometry. It also offers efficient storage and retrieval of spatial data by reducing the space required to store data by as much as 40 percent.

The ArcSDE Compressed Binary storage type can be used to store geometry in ArcSDE geodatabases in Oracle or Microsoft SQL Server databases. It is the primary storage type for ArcSDE geodatabases stored in SQL Server and was previously the default storage type for ArcSDE geodatabases stored in Oracle prior to ArcGIS 9.3.

A compressed binary feature class is made up of three tables: the business table, feature table, and spatial index table.

The business table contains attributes and a spatial column. The spatial column is a key to the feature and spatial index tables.

The relationship between the business table and feature table is managed through the spatial column and the feature ID (FID) column. This key, which is maintained by ArcSDE, is unique.

For further description of feature classes stored in the ArcSDE Compressed Binary format, see Feature classes in a geodatabase in SQL Server and Feature classes in a geodatabase in Oracle.

ArcSDE Compressed Binary in SQL Server

In SQL Server databases, ArcSDE Compressed Binary is the default geometry storage. In ArcGIS 9.3 and lower releases, ArcSDE Compressed Binary storage in SQL Server is stored as an image data type. New data created using ArcSDE Compressed Binary storage in SQL Server at ArcGIS 10 and later releases is stored as a varbinary(max) data type.

The DBTUNE table parameter GEOMETRY_STORAGE defines the geometry storage format of a feature class. In geodatabases in SQL Server, the GEOMETRY_STORAGE value for the default is SDEBINARY. Under the DEFAULTS keyword in the dbtune.sde file, the GEOMETRY_STORAGE is set to SDEBINARY.

##DEFAULTS

GEOMETRY_STORAGE "SDEBINARY"

<other parameters>

END

You can change the default GEOMETRY_STORAGE in a geodatabase in SQL Server to use Microsoft's Geometry or Geography spatial types or the Open Geospatial Consortium (OGC) Well-Known Binary storage data type by changing the value of the GEOMETRY_STORAGE parameter of the DEFAULTS keyword to OGCWKB. For a description of these data types, see ArcSDE and the Microsoft spatial types and The OGC Well-Known Binary representation for geometry.

If you have changed your DEFAULTS GEOMETRY_STORAGE to something other than SDEBINARY but want to create some of your feature classes with ArcSDE Compressed Binary, you could create a configuration keyword to specify when you create specific feature classes. For example, in the dbtune.sde file, such a configuration keyword might appear as follows:

##SDEBINARY

GEOMETRY_STORAGE "SDEBINARY"

UI_TEXT ""

COMMENT "Used to create feature classes with SDEBINARY geometry storage"

END

For information on creating DBTUNE keywords, see Custom configuration keywords.