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You can extend these by creating your own custom objects with custom behaviors. In addition you have geodatabase specific types/behaviors described below. | You can extend these by creating your own custom objects with custom behaviors. The following sections describe geodatabase specific types/behaviors described below. == Point Features == |
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== Line Features == Lines are built from three kinds of segments: * Line segments (straight) * circular arcs * Bezier splines Line features can have custom drawing behavior that generalizes the line depending on the map scale or that controls the placement of annotation along the line. == Network edge features == |
GeoDatabases
GeoDatabases implement an object-based GIS data model (the geodatabase data model). Each feature is stored in a row in a table that contains common features (lines, polygons, etc.). The vector shape of the feature is stored in the tables's shape field with feature attributes in other fields. this is probably what we want to use for our Archaeology project!
In addition, GeoDatabases can store raster images, data tables, and references to other tables. GeoDatabases can hold all your data in one location! They are like adding coverages, shapefiles and raster images into a DBMS.
Geodatabases can have build-in behavior; geodatabase features are completely stored in a single database; and large geodatabase feature classes can be stored seamlessly, not tiled.
Basic objects are:
- points
- lines
- areas
- multi-[point|line|area]
You can extend these by creating your own custom objects with custom behaviors. The following sections describe geodatabase specific types/behaviors described below.
Point Features
Network Junction Features are points that play a topological role in a network (somewhat like nodes in coverages) and come in two flavors: Simple and Complex.
- Simple junction features might be used to represent a fitting that connects two pipes. It could have validation behavior that would ensure that connected pipes are of the correct diameter and materials.
- Complex junction features plays a more complex role in a network and may for instance represent an electric switch that in position (a) connects A-B and in position (b) connects A-C
B | | A --------- C
Line Features
Lines are built from three kinds of segments:
- Line segments (straight)
- circular arcs
- Bezier splines
Line features can have custom drawing behavior that generalizes the line depending on the map scale or that controls the placement of annotation along the line.
Network edge features
Geodatabase objects are files that contain Personal Geodatabase FeatureDatasets. FeatureDatasets contain related objects