.. _vector.filegdb:

ESRI File Geodatabase (FileGDB)
===============================

.. shortname:: FileGDB

.. build_dependencies:: FileGDB API library

The FileGDB driver provides read and write access to vector layers of
File Geodatabases (.gdb directories) created by ArcGIS 10 and above. The
dataset name must be the directory/folder name, and it must end with the
.gdb extension.

Note : the :ref:`OpenFileGDB
driver <vector.openfilegdb>` driver exists as an alternative
built-in i.e. not depending on a third-party library) read-only driver.

Driver capabilities
-------------------

.. supports_create::

.. supports_georeferencing::

Requirements
------------

`FileGDB API SDK <http://www.esri.com/apps/products/download/#File_Geodatabase_API_1.3>`__

Curve in geometries are supported on reading with GDAL >= 2.2.

Bulk feature loading
--------------------

The FGDB_BULK_LOAD configuration option can be set to YES to speed-up
feature insertion (or sometimes solve problems when inserting a lot of
features (see http://trac.osgeo.org/gdal/ticket/4420). The effect of
this configuration option is to cause a write lock to be taken and a
temporary disabling of the indexes. Those are restored when the
datasource is closed or when a read operation is done.

Bulk load is enabled by default for newly
created layers (unless otherwise specified).

SQL support
-----------

SQL statements are run through the SQL engine of
the FileGDB SDK API. This holds for non-SELECT statements. However, due
to partial/inaccurate support for SELECT statements in current FileGDB
SDK API versions (v1.2), SELECT statements will be run by default by the
OGR SQL engine. This can be changed by specifying the *-dialect FileGDB*
option to ogrinfo or ogr2ogr.

Special SQL requests
~~~~~~~~~~~~~~~~~~~~

"GetLayerDefinition a_layer_name" and "GetLayerMetadata a_layer_name"
can be used as special SQL requests to get respectively the definition
and metadata of a FileGDB table as XML content.

Transaction support
-------------------

The FileGDB driver implements transactions at the database level,
through an emulation (as per :ref:`rfc-54`),
since the FileGDB SDK itself does not offer it. This works by backing up
the current state of a geodatabase when StartTransaction(force=TRUE) is
called. If the transaction is committed, the backup copy is destroyed.
If the transaction is rolled back, the backup copy is restored. So this
might be costly when operating on huge geodatabases.

Starting with GDAL 2.1, on Linux/Unix, instead of a full backup copy
only layers that are modified are backed up.

Note that this emulation has an unspecified behavior in case of
concurrent updates (with different connections in the same or another
process).

CreateFeature() support
-----------------------

The FileGDB SDK API does not allow to create a feature with a FID
specified by the user. Starting with GDAL 2.1, the FileGDB driver
implements a special FID remapping technique to enable the user to
create features at the FID of their choice.

Dataset Creation Options
------------------------

None.

Layer Creation Options
----------------------

-  **FEATURE_DATASET**: When this option is set, the new layer will be
   created inside the named FeatureDataset folder. If the folder does
   not already exist, it will be created.
-  **LAYER_ALIAS**\ =string: (GDAL >=2.3) Set layer name alias.
-  **GEOMETRY_NAME**: Set name of geometry column in new layer. Defaults
   to "SHAPE".
-  **GEOMETRY_NULLABLE**: (GDAL >=2.0) Whether the values of the
   geometry column can be NULL. Can be set to NO so that geometry is
   required. Default to "YES"
-  **FID**: Name of the OID column to create. Defaults to "OBJECTID".
   Note: option was called OID_NAME in releases before GDAL 2
-  **XYTOLERANCE, ZTOLERANCE**: These parameters control the snapping
   tolerance used for advanced ArcGIS features like network and topology
   rules. They won't effect any OGR operations, but they will by used by
   ArcGIS. The units of the parameters are the units of the coordinate
   reference system.

   ArcMap 10.0 and OGR defaults for XYTOLERANCE are 0.001m (or
   equivalent) for projected coordinate systems, and 0.000000008983153°
   for geographic coordinate systems.

-  **XORIGIN, YORIGIN, ZORIGIN, XYSCALE, ZSCALE**: These parameters
   control the `coordinate precision
   grid <http://help.arcgis.com/en/sdk/10.0/java_ao_adf/conceptualhelp/engine/index.html#//00010000037m000000>`__
   inside the file geodatabase. The dimensions of the grid are
   determined by the origin, and the scale. The origin defines the
   location of a reference grid point in space. The scale is the
   reciprocal of the resolution. So, to get a grid with an origin at 0
   and a resolution of 0.001 on all axes, you would set all the origins
   to 0 and all the scales to 1000.

   *Important*: The domain specified by
   ``(xmin=XORIGIN, ymin=YORIGIN, xmax=(XORIGIN + 9E+15 / XYSCALE), ymax=(YORIGIN + 9E+15 / XYSCALE))``
   needs to encompass every possible coordinate value for the feature
   class. If features are added with coordinates that fall outside the
   domain, errors will occur in ArcGIS with spatial indexing, feature
   selection, and exporting data.

   ArcMap 10.0 and OGR defaults:

   -  For geographic coordinate systems: XORIGIN=-400, YORIGIN=-400,
      XYSCALE=1000000000
   -  For projected coordinate systems: XYSCALE=10000 for the default
      XYTOLERANCE of 0.001m. XORIGIN and YORIGIN change based on the
      coordinate system, but the OGR default of -2147483647 is suitable
      with the default XYSCALE for all coordinate systems.

-  **XML_DEFINITION** : When this option is set, its
   value will be used as the XML definition to create the new table. The
   root node of such a XML definition must be a <esri:DataElement>
   element conformant to FileGDBAPI.xsd
-  **CREATE_MULTIPATCH**\ =YES : When this option is set,
   geometries of layers of type MultiPolygon will be written as
   MultiPatch
-  **CONFIGURATION_KEYWORD**\ =DEFAULTS/TEXT_UTF16/MAX_FILE_SIZE_4GB/MAX_FILE_SIZE_256TB/GEOMETRY_OUTOFLINE/BLOB_OUTOFLINE/GEOMETRY_AND_BLOB_OUTOFLINE
   : Customize how data is stored. By default text in
   UTF-8 and data up to 1TB

Examples
--------

-  Read layer from FileGDB and load into PostGIS:
-  Get detailed info for FileGDB:

Building Notes
--------------

Read the `GDAL Windows Building example for
Plugins <http://trac.osgeo.org/gdal/wiki/BuildingOnWindows>`__. You will
find a similar section in nmake.opt for FileGDB. After you are done, go
to the *$gdal_source_root\ogr\ogrsf_frmts\filegdb* folder and execute:

``nmake /f makefile.vc plugin         nmake /f makefile.vc plugin-install``

Known Issues
------------

-  The SDK is known to be unable to open layers with particular spatial
   reference systems. This might be the case if messages "FGDB: Error
   opening XXXXXXX. Skipping it (Invalid function arguments.)" when
   running "ogrinfo --debug on the.gdb" (reported as warning in GDAL
   2.0). Using the OpenFileGDB driver will generally solve that issue.
-  FGDB coordinate snapping will cause geometries to be altered during
   writing. Use the origin and scale layer creation options to control
   the snapping behavior.
-  Driver can't read data in SDC format (Smart Data Compression) because
   operation is not supported by the ESRI SDK.
-  Reading data compressed in CDF format (Compressed Data Format)
   requires ESRI SDK 1.4 or later.

Links
-----

-  `ESRI File Geodatabase API
   Page <https://github.com/Esri/file-geodatabase-api/>`__
-  :ref:`OpenFileGDB driver <vector.openfilegdb>`, not depending on a
   third-party library/SDK
