Thematic Map Modeling
نویسندگان
چکیده
We study here how to provide the designer of geographic databases with a database query language extensible and customizable. The model presented here is a rst step toward a high level spatial query language adapted to the manipulation of thematic maps. For this, we take as an example a toy application on thematic maps, and show by using a complex objects algebra that application dependent geometric operations can be expressed through an extension of the replace operator of AB88].
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