2011

Overview of Bringing In GIS Features
This map of a water distribution system is made up of features stored in a set of SDF
files.
NOTE This topic applies to geospatial data. To bring in drawing (DWG) objects,
see
Overview of Bringing in Drawing Data From DWG Files (page 351).
A feature is the spatial description of a real-world entity such as a road, a utility
pole, or a river. Features are stored in a spatial database or file. The spatial
database or file is referred to as a
feature source (page 2063).
The feature source could be a database (such as Oracle, ArcSDE, SQL Server,
or MySQL), a file-based feature source (such as SDF or SHP), a web server (such
as WFS), or a table of feature geometry data (such as Microsoft Access).
Once you connect to a feature source, you select the types of features to include
in your map. Each type of feature is called a
feature class (page 2063). AutoCAD
Map 3D displays all the features from the selected features classes in your map,
and each feature class becomes a layer in Display Manager. For example, a
feature class called Roads contains individual streets and appears on a layer
called Roads in Display Manager. You can apply a single style to this layer,
and all the streets in the layer will use that style.
A
schema (page 2073) is the definition of multiple feature classes and the
relationships between them. It determines the criteria an individual feature
must meet in order to be a member of a particular feature class. For some
feature sources, you can add and edit a schema and its feature classes and
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