.. Data Model Overview
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  # Project: EOxServer <http://eoxserver.org>
  # Authors: Stephan Krause <stephan.krause@eox.at>
  #          Stephan Meissl <stephan.meissl@eox.at>
  #          Martin Paces <martin.paces@eox.at>
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.. _Data Model Overview:

Data Model
==========

The core resources in EOxServer are coverages, more precisely GridCoverages. 
The EOxServer data model adopts and strongly relates to the data model from 
EO-WCS (OGC 10-140) as shown below in Figure: ":ref:`fig_eo-wcs_data_model`".

.. _fig_eo-wcs_data_model:
.. figure:: images/EO-WCS_Data_Model.png
   :align: center

   *EO-WCS Data Model from OGC 10-140*

.. _Coverages Data Model:

Data Integration Layer
----------------------

Figure: ":ref:`fig_model_coverages`" below shows the data model of the coverage resources.
Note the correlation with the EO-WCS data model as shown above.

.. _fig_model_coverages:
.. figure:: images/model_coverages.png
   :align: center

   *EOxServer Data Model for Coverage Resources*

Data Access Layer
-----------------

Figure: ":ref:`fig_model_backends`" below shows the data model of the back-ends layer.

.. _fig_model_backends:
.. figure:: images/model_backends.png
   :align: center

   *EOxServer Data Model for Back-ends*

.. _ATP Data Model:

Task Tracker Data Model 
-----------------------

*Asynchrounous Task Processing* (ATP) uses its own DB model displayed in Figure:
":ref:`fig_model_processes`" to implement the task queueu, store the task inputs
and outputs and track the tasks' status. (For more detail on ATP subsystem see
":ref:`atp_sum`").

.. _fig_model_processes:
.. figure:: images/model_processes.png
   :align: center

   *EOxServer Data Model of ATP Task Tracker*