Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/GDB|GeoGateway+Data+Model">GeoGateway Data Model</a><hr>
<H4>A GeoGateway Database</H4>
Within GeoGateway there are frequent references to GeoGateway databases.
In GeoGateway a database is a grouping of data layers, usually referring
to the contents of a single file. It does not normally mean a database
in the RDBMS sense, such as Oracle, Microsoft Access, or DBase.<p>
For GeoGateway purposes we define a database as a grouping of data layers,
and associated auxiliary information. Each GeoGateway database has a name,
normally the name of the primary file defining the database. Given a 
database name from the user, GeoGateway applications can open the database,
read and/or write a variety of data, and eventually close the database again.<p>
A database can contain raster layers (channels), vector layers (or segments),
lookup tables (LUTs), pseudocolour tables (PCTs), ground control points(GCPs),
a projection definition, metadata, and a variety of other auxiliary 
information.<p>
Each channel of raster data or segment is considered to be a Layer in
GeoGateway. This includes things like GCP segments and LUTs, for which
the name layer seems inappropriate. However, it does not include the
projection definition (even though this is a segment in PCIDSK).
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Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/GDB|GeoGateway+Data+Model">GeoGateway Data Model</a><br>
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