SPATIAL DATABASES

In an Object Oriented environment, each theme or spatial data type is materialized by a class. Complex objects are obatined from atomic objects by using basic constructors set and tuples.

Class State tuple ( sname string, counties: set (County))

Class County tuple ( cname string, pop integer, state_in_county: State area region)

 

Like SDT, in the object oriented model spatial primitives are defined by classes.

Class Point tuple (x: real, y: real)
Class Line list (tuple (x: real, y: real))
Class Region set( list (tuple (x: real, y: real)))
Class Node tuple (x: real, y: real, endpoints: list (arc))
Class Arc tuple (origin: Node, destination: Node,
left: Polygon , right: Polygon
vertice: list (tuple (x: real, y: real)))

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