Querying over genomic ranges
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InterMine includes functionality for querying features with overlapping genome coordinates.  We have an index that is created on the `Location` table.  This is used by a 'virtual' `SequenceFeature.overlappingFeatures` collection that is a `view` in the postgres database using the native `Postgres index <https://www.postgresql.org/docs/9.5/static/rangetypes.html>`_ to find other features that overlap it.

In modMine (the InterMine for the modENCODE project) we also create `GeneFlankingRegion` features to represent specific distances upstream and downstream of genes to query for genes that are nearby other features. 

Create the index
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You need to create the index on the location table in your production database by adding the `create-location-range-index` post-process step to your `project.xml` file:

.. code-block:: xml

	<post-process name="create-location-range-index"/>

Create the overlappingFeatures view
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Create the `SequenceFeature.overlappingFeatures` view in the database. This allows you to query for any features that overlap any other types of features in the web interface or query API.  Add the `create-overlap-view` post-process step, which needs to be located **after** `create-location-range-index` in your project XML file.

.. code-block:: xml

	<post-process name="create-overlap-view" />

Now any queries on the `overlappingFeatures` collections will use this view and the new index.

.. index:: overlaps, region search, bioseg, genome coordinates, overlappingFeatures, create-overlap-view, create-bioseg-location-index