2011

Table Of Contents
limitations in SQL Server. The data itself is not altered and can still be
queried by an external application. You can later delete the metadata table.
NOTE It is recommended that you use FDO-enabled schemas only if you need
their additional capabilities. Otherwise, choose the default, non-FDO-enabled
schema.
Selecting a Coordinate System for a Spatial Context
Once you create a data store, you create and apply a schema to it. The schema
defines the table and columns into which you will put data. For FDO geometry
properties, there are two possible SQL Server Spatial column types: geometry
and geography. The geography type is used for geodetic (lat/long) coordinate
systems and the geometry type is used for non-geodetic coordinate systems.
For both, a spatial index with default parameters is created automatically.
SQL Server Spatial includes a catalog of geodetic coordinate systems, but not
non-geodetic coordinate systems. Both geometry and geography column types
save SRID values, but only geography type columns reference an entry in the
catalog, and in this case the SRID numbers are EPSG numbers.
In AutoCAD Map 3D, when you define a spatial context, you select a
coordinate system from the Mentor catalog. To use this coordinate system
with SQL Server Spatial, AutoCAD Map 3D must translate the coordinate
system information from Mentor into an SRID. SRID is the only identifier that
SQL Server can use for both geodetic and non-geodetic coordinate systems.
AutoCAD Map 3D uses the EPSG code of the coordinate system as the SRID.
The spatial context creation can fail if either of the following is true:
The coordinate system does not have an EPSG code.
The coordinate system is in the SQL Server catalog but its SQL Server WKT
definition is not recognized by Mentor.
To resolve these situations, use a translation table in the file
ExtendedCoordSys.txt. By default, this file is stored in FDO\bin\com in the
AutoCAD Map 3D installation folder.
If the coordinate system does not have an EPSG code, add it to
ExtendedCoordSys.txt and specify an SRIDfor it. Choose an SRID number that
is not an EPSG code. The ExtendedCoordSys.txt file contains instructions for
doing this.
If the SQL Server WKT definition is not recognized by mentor, add the
coordinate system to ExtendedCoordSys.txt (if it is not already there) and set
Creating FDO-Enabled SQL Server Spatial Data Stores | 591