AN-ALTERNATIVE TECHNIQUE FOR UPDATING DIGITAL MAP DATA 
WITHIN A PILOT PROJECT IN EGYPT 
Dr. OSMAN A.A AKIF PROF. DR. MOHAMED M. NASSAR 
LECTURER OF SURVEYING PROFESSOR OF SURVEYING AND GEODESY 
AND PHOTOGRAMMETRY FACU. OF ENG. AIN SHAMS UNIVERSITY. 
FACULTY OF ENG., AIN 
SHAMS UNIVERSITY 
PROF. DR. MONA EL KADY ENG. KHALED M. HASSEN 
DIRECTOR OF SURVEY RESEARCHER IN SURVEY 
RESEARCH INSTITUTE RESEARCH INSTITUTE 
WATER RESEARCH CENTER WATER RESEARCH CENTER 
308 EL AHRAM STREET 308 EL AHRAM STREET 
GIZA , EGYPT . GIZA , EGYPT . 
ISPRS COMMISSION: IV 
ABSTRACT : 
The updating of digital maps has always been a time consuming task, one that many organizations either have 
avoided or deferred for years. Digital mapping technology offers the promise of easier-- and therefore, 
the potential for more frequent updating.Improvements: have been made in creating interactive graphic editi- 
ng and updating capabilities, yet not all updating scenarios have lent themselves to make such updating fr- 
om the database management system ( DBMS ). 
We have tested non-graphic updating procedures in a pilot area of 1.5 square kilometers in Giza city in 
Egypt using ESRI'S ARC/INFO on Micro-Vax computers. The Users recognize that coverage's graphics are maint- 
ained separatly from the user-accesable attibute database ( INFO files ). This is done for good reasons 
which are not questioned here. What we have tested here is an alternative technique for allowing updating 
to coordinates and topologies through INFO DBMS without low-level binary management of the graphic files. 
The proposed technique uses ARC AMLs only and allows linkage to be managed entirely by high-level arc 
routines. 
The primary advantage of such technique is that it allows the u 
nates changes with topologies and vise versa. In addition, 
potential in improving the interfaces between existing digit 
or digital information from external updating sources such a 
pdating to be expressed as automatic coordi- 
the developed technique will have significant 
al maps and any external non-graphic database 
S total station, remotely sensed imagery,..etc. 
KEY WORDS : Database Models, DBMS, Digital Mapping, Egypt, Spatial Database queries, Topology. 
INTRODUCTION 
The problem of growth an economic expention fased Egypt has recently moved towards fully implementing 
by planners and mapping organization and the corre- digital mapping and Geographic/Land Information 
sponding need for rapid access to map data have led Systems throughout the country. One of the major 
to the development of digital mapping technology. problems that has been encountered is to update the 
Digital mapping can be defined as the digital repr- existed old maps which are not in digital form. Th- 
esentation of the spatial and/or the planimetric erefore, many researches have been conducted to 
distribution of map characteristics. It contains find out the most convenient technique for updating 
spatial information such as the location of differ- these existing old maps. This study is one of these 
ent map entities, and non-spatial information such researches which aims mainly to update the large 
as feature codes attached to the spatial informat- scale digital maps within the Egyptian circumsta- 
ion to be identified in the digital form [Cooper nces from the topological attribute records stored 
1989; Akif 1990]. in the DBMS and using ESRI s ARC/INFO software mod- 
ules and many other routines developed in ARC MACRO 
In GIS/LIS, digital maps generally are formatted as Language (AML). 
either vector or raster data. Vector data describe 
areal features as polygons and linear features as INTIGRATED VERSUS LINKED ATTRIBUTE 
line seggments, both composed of digital points GRAPHICS IN DBMS 
whose locations are expressed in coordinates. On 
the other hand, raster data partition land parcel The Database management system (DBMS) constitutes 
into a regular grid with location specified by add- one of the backbone components of any GIS/LIS. The 
ress or row and column numbers, [Wallace et al. objectives of any DBMS is to enable the user for 
1988]. Moreover, Vector format data in the form of a quick and easy access to data held within the 
topological facts and metric location and shape system free from complexity of data storage, searc- 
create an even more explicit digital map. A topolo- hing, sorting or updating mechanism. Many database 
gical data structure enables the construction of a management strategies depend upon a knowledge of 
consistent digital map that contains relations the specific form of queries that are to be handled 
among features which provides capability to edit prior to data entry such as hierarcical and network 
vector data and ensure logical consistency and database models, [Date, 1990]. A relational data- 
hence is essential in the creation of digital map base on the other hand which is used in this resea- 
files, [Spooner, 1989]. rch enables the user to develop different uses and 
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