About geometry storage types

About geometry storage types
Release 9.3

Physical storage of geometry for features is managed using standard data types. The geometry storage types available for you to use depend on what database management system (DBMS) you have. Some have spatial data types while others provide standard binary or binary large object (BLOB) storage types. A summary of the available storage types by DBMS are listed in the table below.

DBMS	Geometry Storage	Column Type	Notes
DB2	Spatial Extender—Geometry Object	ST_Geometry*	Utilizes extended spatial type for managing vector data Based on the ISO SQL MM specification for spatial; built in concert with ESRI
Informix	Spatial DataBlade—Geometry Object	ST_Geometry*	Utilizes extended spatial type for managing vector data Based on the ISO SQL MM specification for spatial; built in concert with ESRI
Oracle	Spatial Type for Oracle—Geometry type	ST_Geometry*	Utilizes extended spatial type for managing vector data Based on the ISO SQL MM specification for spatial Default geometry storage for ArcSDE for Oracle
	Well-Known Binary (OGCWKB)	BLOB	OGC simple features type
	ArcSDE Compressed Binary	LONG RAW or BLOB	Provides high performance, scalability, and reliability
	Oracle Spatial—Geometry Type	SDO_Geometry	Oracle Spatial users can optionally use the SDO_Geometry column type. You can make this decision on a table by table basis, so you can choose the best option for each individual dataset.
PostgreSQL	Spatial type for PostgreSQL	ST_Geometry*	Utilizes extended spatial type for managing vector data Based on the ISO SQL MM specification for spatial Default geometry storage for ArcSDE for PostgreSQL
	PostGIS	Geometry	PostGIS users can choose to use the PostGIS geometry column type. This type follows the OpenGIS Simple Features Specification for SQL.
SQL Server**	ArcSDE Compressed Binary	Image	The binary type fully manages complex binary streams required for complex line and polygon features found in typical and advanced GIS applications. The default geometry storage for ArcSDE geodatabases for SQL Server.
	Well-Known Binary (OGCWKB)	Image	OGC simple features type
	Microsoft SQL Server Geometry type	Geometry	One of the Microsoft SQL Server spatial storage types Provides a spatial type for managing vector data that is defined by coordinates on an arbitrary plane and for which the curvature of the Earth does not need to be taken into account
	Microsoft SQL Server Geography type	Geography	One of the Microsoft SQL Server spatial storage types Provides a spatial type for spatial data that is defined by latitude and longitude coordinates and for which the curvature of the Earth does need to be taken into account

*ST_Geometry is a superclass comprising several instantiable subclasses.

**Geodatabases created on database servers (SQL Server Express instances) use the ArcSDE compressed binary storage type; you cannot specify another geometry storage type.

For DBMSs that allow multiple types of storage options, you could use any combination of available storage methods. For example, you may choose to store a point layer as Oracle Spatial geometry type and a polygon layer as ST_Geometry type.

That is where the geometry configuration parameters of the DBTUNE table come in. For geodatabases stored in Oracle, SQL Server, or PostgreSQL, there are configuration values you can set to specify which geometry storage to use.

To set the default geometry storage type—the one that you would use for most of your data—you would alter the value of the GEOMETRY_STORAGE parameter under the DEFAULTS configuration keyword in the DBTUNE table. You can also create separate geometry storage keywords that specify different geometry storage types. You can then use these keywords when creating or importing data to the geodatabase, thereby storing that data using a storage type other than the one specified in DEFAULTS.

Spatial types

A spatial type embeds support for GIS feature geometry into the DBMS kernel. Some DBMSs that support spatial types comply with the OpenGIS SQL specification for user-defined types (UDTs) and the ISO SQL Multimedia Spatial Standard. These standards define columns capable of storing spatial data such as the location of a landmark, a street, or a parcel of land. Use of these spatial types integrates geometry and nonspatial attributes, providing a single point of access inside the DBMS through a SQL API. Informix and IBM DB2 support spatial types. The Spatial Type for Oracle and PostgreSQL, which use an ST_Geometry type, are also spatial types, as is Oracle Spatial and the PostGIS geometry type. For spatial types, geometry is stored in the business table.

NOTE: ESRI recommends you do not use SQL commands to alter the geometry storage type of a dataset after it has been created.

About geometry storage types

About geometry storage types

See Also