Labels:text | screenshot | yellow | rectangle | font OCR: The Evolution of Geographical Information Systems N FIRST GENERATION GISS, THE GIS SOFTWARE RUNG AS AN APPLICATION ON TOP of a file system All GIS data and indexes are storedin flat fles and it is the GIS soft ware that manages that data The limitation of this architecture is that it only handles. spatial data, Application code is required to combine spatial data with other business data. The next step in the evolution is to give Jata managuunent responsibilities to a DBMS, The GIS can work with the DBMS to store Gis data and attributes in the relational :alles, This does give you the ability to generate more complex queries But you are still using a proprietary GIS API to access and analyze spat al data and it puts more of a burden on XDBAS, who must manage both systems A fully integrated GIS is really just another part of the DBIVS. Spatial data is simply un other data type, and you can generate sophisticated queries and take advantage of the DBMS's cost-based optimize, The DBA does not have to worry about managing a sepa- rate system. First generation Spatial data Proprietary Proprietary stored in GIS APS GIS API file system Spatial data Second generation Proprietary GIS API in external BLOBS in DBMS Proprietary GIS API Traditional data SOL Third generation Extendedl RDBMS that understands Spatial data SOL stored as ADTs in DBMS with traditional data
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