Each industry model can have a single coordinate system. (In Oracle, coordinate systems are called SRIDs). A project can contain multiple industry models, each of which uses a different coordinate system (or no coordinate system). The industry model coordinate system automatically applies to all feature classes of the industry model. You can join database schemas with non-matching coordinate systems.
The support for coordinate systems covers graphic generation and graphic editing (digitizing with back transformation of the digitized coordinates). During graphic generation, when a project contains several industry models with different coordinate systems, the coordinate system is used for on-the-fly coordinate transformation, representing the geometry data in AutoCAD Map 3D toolset in one global coordinate system.
You can set the coordinate system (SRID) for all feature classes of an industry model. For example, to add an industry model with no coordinate system to a project that contains an industry model with a coordinate system, you must assign a coordinate system to the incoming industry model.
If the industry model contains views with relations to external tables, you cannot update the coordinate system.
Note: In addition to the industry models, each drawing uses its own coordinate system. When you connect to other data stores using Data Connect, they may have different coordinate systems as well, but they are transformed to the drawing’s coordinate system automatically. The original data store remains unchanged
The same thing happens when you represent enterprise industry model data in a drawing. Although the representation is transformed in the drawing, all calculations and geometry updates are made in the industry model coordinate system. Also, the coordinate values shown in the Maintenance workspace dialog boxes and feature class forms are the internal database values.
For more information about SRIDs in Oracle, see Oracle Spatial Users Guide and Reference.