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GEOGRAPHICAL DATABASE - STRUCTURES 
OSVALDO ARI ABIB - BRAZIL 
ABSTRACT 
The data management is the of great importance to Geographic Information System, 
therefore often it needs help from a Database Management System - DBMS. 
Normaly, the DBMS that may be obtained are not prepared to work with complex structures. 
This work is about the mainly adaptation 
cartographic view in developing Geographic Database. 
1. INTRODUCTION 
The volume of information available for 
those responsable for the Politics, 
economics, environmental and social 
decisions is very large. In all aspects of 
the human knowledge, the amount and speed 
of the data update grow very much. This 
data, due to its volume, is not used in a 
Proper way and sometimes not used at all. 
When we introduce the geographical 
element, the quantity of data increases 
even more making its use almost 
impossible. 
Another important problem is the 
information access. The process used to 
enable this access must be rapid and 
reliable enough so that information will 
prove to be usefull. 
The solution for the logical use of the 
information is the application of the 
Database technology. 
In the same way, with the joint of the 
geographical information, we have the 
Geographical Database-GDB, which relates 
the literal information with the 
geographical. To do this, in the 
beginning, single adjusts were used for 
the Convencional Database-CDB, what 
normally, its not a good solution. 
This work introduces the principal focus 
about Geographical Database and the trends 
about this technology. 
2. THE GIS CONCEPTION 
One may think a GIS as an Information 
System, whose functions are the 
acquisition, management, analisys and 
presentation of the information spaciously 
organized about a certain region. 
From de above idea, one of the most 
important GIS function is the information 
management, usually executed with help of 
one Database Structure. 
3. THE GDB E CDB DIFFERENCES 
A database can be defined as a collection 
of the real world representation in form 
Of related data, as coherent as Possible, 
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that we have to do to DBMS and, the 
stored with controlled redundance and 
structured in way to facilitate its usage 
and to satisfy a large variety of demands. 
This concept has been widely used in 
commercial applications, denoting mainly 
the sistematic aspect. When we introduce a 
new element, the geographical feature, we 
have the Geographical Database, which has 
a close association with the literal and 
geographical information. 
The objects that belong to the GDB, 
although having more information, must be 
manipulate as only one unit of Processing. 
The mentioned objects are normaly called 
complex objects. 
The main differences among the objects 
belonging to GDB and CDB are: 
- The CDB records are usually of fixed 
length, whereas the GDB records have 
variable length or one chain of records 
for store long objects; 
- The data volume for the GDB is larger 
than the used for the CDB; 
- In the GDB, the number of records in 
the same entity is big, but the number of 
entity is small, occuring the contrary in 
the CDB; 
- The query languages and the access 
methods used by both are differents; 
- The GDB stores, beyond of his data, 
its topology. 
4. THE MAIN REPRESENTATIONS 
In this part, the main representations for 
complex objects will be represented, from 
the simplest to the most recent researchs 
on this topic. 
The first two representations have both 
the literal and the geographical data 
separated, while the others have them 
together. 
4.1 Iext File 
This approach has all the literals data 
stored in specific files or in a database 
which has a external interface. The 
graphics data are stored in specifics 
structures and also has a extern