Leveraging your database to manage spatial data
Jason Weinberger
MapInfo Corporation
1 Global View, Troy, NY 12180
Abstract
Relational Database Management Systems have become the backbone of today’s
commercial and government IT infrastructure. Databases allow government to offer
citizens self-service tools and empower e-government. Traditionally databases are able
to store textual and numeric data. This data can include everything from property values
to school district information to dog licenses. Virtually any information that government
uses in an operational setting can be stored and accessed through the use of the leading
commercial database products. Until recently databases could not do anything with
spatial data. Today, several database vendors have begun to offer spatial capabilities to
their products either as add on components or included with the initial database purchase.
Many GIS vendors also offer spatial database tools. Adding spatial capabilities to the
RDBMS gives users a new wealth of functionality that was never previously available.
Spatial databases can be used to facilitate e-government to determine if a citizen’s
election district and direct the citizen to the appropriate polling place. It can be used for a
call before you dig application to track easements. It can also be used to store and track
street networks and property boundaries.
What can be done without a spatial database?
Using virtually any database that support open standards such as ODBC and
JDBC can be used to store point data. For instance an address can be assigned a latitude
and longitude value, which can then be stored as two columns inside of the database.
Most GIS products are able to interpolate these columns as spatial points and users can
extract this data and manipulate it inside of their GIS software. Additional GIS tools are
required in order to utilize this data. The database does not recognize these points as
having spatial value. The database is only able to recognize these points as numeric
values.
Without spatial capabilities the database cannot do anything beyond serving as a
data store for point information. It cannot manipulate the data without additional GIS
tools. It cannot store data such as lines and polygons, which often represent things such
as roads and election districts. Without a spatially enabled database the capabilities
available to the user are quite limited.
What are the core components of a spatial database?
Although different vendors approach spatially enabling the database in different
ways, there are several key components that must be present in order to fully leverage the
power of the database to manage spatial data. There are three main components that
should be present as part of the spatial relational database management system. These
components include a spatial data type, a spatial indexing scheme and spatial operators.
