.. _filegdb:

*****************************************************************************
 ESRI File Geodatabase
*****************************************************************************

ESRI File Geodatabases exist in a file folder and offer improved performance and size limitations.  For more information see the ESRI `description page`_.

.. _`description page`: http://resources.arcgis.com/content/geodatabases/10.0/types-of-geodatabases 

.. note::
   Only file geodatabases created by AcrGIS 10.0 and above can be read by GDAL/MapServer.

File listing
------------

File geodatabases are made up of a set of files within a folder. The files are made up of geographic data, attribute data,
index files, and lock files.  A better description of the file contents can be found `here <http://webhelp.esri.com/arcgisserver/9.3/java/index.htm#geodatabases/file_ge-516860750.htm>`__.

Data Access / Connection Method
---------------------------------

File geodatabase access is available through OGR. See the OGR `driver page <http://www.gdal.org/ogr/drv_filegdb.html>`__
for specific driver information.  The driver is available for GDAL >= 1.9.0.

The CONNECTION parameter must be used to point to the name of the file folder, and the DATA parameter
should be the name of the spatial table (or OGR layer).

::

  CONNECTIONTYPE ogr
  CONNECTION "filegdb-folder"
  DATA "layername" 
  
.. note::
   The CONNECTION path is relative to the mapfile (SHAPEPATH is not used here).  Full paths can also be used.

OGRINFO Examples
----------------

First you should make sure that your GDAL/OGR build contains the file
geodatabase "FileGDB" driver, by using the '--formats' command:

::

  >ogrinfo --formats
     Supported Formats:
     ...
     "FileGDB" (read/write)
     "ESRI Shapefile" (read/write)
     "MapInfo File" (read/write)
     "UK .NTF" (readonly)
     "SDTS" (readonly)
     "TIGER" (read/write)
     ...

If you don't have the driver, see GDAL's `BuildHints <http://trac.osgeo.org/gdal/wiki/FileGDB>`__ page for 
compiling the driver.

Once you have the FileGDB driver you are ready to try an ogrinfo command on your
database to get a list of spatial tables.  In the example below our folder is named `us_states.gdb`:

::

  ogrinfo us_states.gdb
    INFO: Open of `us_states.gdb'
    using driver `FileGDB' successful.
    1: statesp020 (Multi Polygon)

Now use ogrinfo to get information on the structure of the `statesp020` table:

::

  ogrinfo us_states.gdb statesp020 -summary
    INFO: Open of `us_states.gdb'
      using driver `FileGDB' successful.

    Layer name: statesp020
    Geometry: Multi Polygon
    Feature Count: 2895
    Extent: (-179.000000, 17.000000) - (179.000000, 71.000000)
    Layer SRS WKT:
    GEOGCS["GCS_North_American_1983",
       DATUM["North_American_Datum_1983",
           SPHEROID["GRS_1980",6378137.0,298.257222101]],
       PRIMEM["Greenwich",0.0],
       UNIT["Degree",0.017453292519943295]]
    FID Column = OBJECTID
    Geometry Column = SHAPE
    AREA: Real (0.0)
    PERIMETER: Real (0.0)
    STATESP020: Real (0.0)
    STATE: String (0.0)
    STATE_FIPS: String (0.0)

Mapfile Example
---------------

.. code-block:: mapfile

    LAYER
      NAME "fgdb_poly"
      TYPE POLYGON
      STATUS ON
      CONNECTIONTYPE OGR
      CONNECTION "../data/filegdb/us_states.gdb"
      DATA "statesp020"
      LABELITEM "STATE"
      CLASS
        NAME "US States"
        STYLE
          COLOR 120 120 120
          OUTLINECOLOR 0 0 0
        END
        LABEL
          COLOR 255 255 255
          OUTLINECOLOR 0 0 0
        END      
      END
    END