The geographies table

This table defines the geographies available for indicators. Each geography type is a set of related polygons that cover some or all of the grid cells. The geography_id distinguishes the different polygons within a particular geography type (geography_type_id). The geography_type_title, at least, will appear in the UrbanSim wizard where the user selects the geography for an indicator.

Column Name	Data Type	Description
geography_type_id	integer	Unique identifier for this geography.
geography_type_title	varchar	A short title describing this geography, e.g. ``district''.
shapefile_path	varchar	Relative path to this ESRI shapefile (relative to the UrbanSim workspace directory).
shapefile_join_column	varchar	The name of the join column in the shapefile for joining the shapes with the geography_ids in the databases.
column_name	varchar	The name of the gridcell table's column containing the data to plot in a JUMP map. Jump gets it as the value of ``org.urbansim.jump.Join Column''.
polygon_id_valid_min	integer	Minimum valid geography_id value for use by this geography.
polygon_id_valid_max	integer	Maximum valid geography_id value for use by this geography.

• geography_type_id must be greater than zero.
• geography_type_id = 1 must be the ``region'' geography.
• geography_type_id = 2 must be the ``grid'' geography.
• geography_type_title must be non-empty with no leading, trailing, or embedded spaces.
• shapefile_path must be non-empty for a map-based visualization to work with this geography.
• polygon_id_valid_min must be greater than zero.
• polygon_id_valid_max must be greater than or equal to polygon_id_valid_min.

This table is copied from the appropriate baseyear or scenario database into the output database, so that it is easily accessible when writing SQL indicator computations.