User's Guide and Reference

Inventory of resources

The resources that you draw on to create spatial columns and manipulate spatial data include:

• Reference data: addresses that DB2 Spatial Extender checks to verify addresses that you want to geocode
• Resources that enable a database for spatial operations: stored procedures, spatial functions, and others
• Non-default geocoders that are provided by users and vendors
• Spatial reference systems

This section discusses reference data and resources that enable a database for spatial operations. For information about non-default geocoders, see About geocoding. For information about spatial reference systems, see About coordinate and spatial reference systems.

Reference data

Reference data consists of the most recent addresses in the United States that the United States Census Bureau has collected. Before the default geocoder can translate an address in your database into coordinates, it must first match part or all of the address to an address in the reference data.

Reference data becomes available to you when you install DB2 Spatial Extender. For the amount of disk space that this data requires, see Disk space requirements. To verify on AIX that the data was loaded properly, look for it in the $DB2INSTANCE/sqllib/gse/refdata/ directory. To verify on Windows NT that the data was loaded properly, look for it in the %DB2PATH%\gse\refdata\ directory.

Resources that enable a database for spatial operations

The first task you perform after installing DB2 Spatial Extender is to enable your database for spatial operations. This involves initiating an action that causes DB2 Spatial Extender to load the database with the following resources:

• Stored procedures. When you request an action from the Control Center, DB2 Spatial Extender invokes one of these stored procedures to execute the action.
• Spatial data types. You must assign a spatial data type to each table or view column in which spatial data is to be stored. For more information, see About spatial data types.
• DB2 Spatial Extender's catalog tables and views. Certain operations depend on the DB2 Spatial Extender catalog. For example, before a column with a spatial data type can be populated, it must be registered in the catalog as a layer. For information about layers, see Developing and implementing a GIS project.
• A spatial index type. It allows you to define indexes for layers.
• Spatial functions. You use these to work with spatial data in a number of ways; for example, to determine relationships between geographic features and to generate more spatial data. One of these functions is a default geocoder. It translates addresses in the United States into coordinates, and then inserts these coordinates into spatial columns. For more information about spatial functions, see Geometries and associated spatial functions and Spatial functions for SQL queries. For more information about the default geocoder, see About geocoding.
• A schema, called DB2GSE, that contains the objects just listed.

For instructions on how to use the Control Center to initiate the loading of these resources, see Enabling a database for spatial operations. For guidelines on using a routine in an application program to perform the same task, see Writing applications for DB2 Spatial Extender.