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The development_events_exogenous table

These development events are changes to grid cells which are scheduled to take place in the future. For any given year, it is possible to schedule any number of changes to the attributes of any number of gridcells. Each change represents that addition of the specified number of sqft, residential units, and improvement values. For example, if GridCell 23 is to grow by 200 residential units in 2008 (an apartment building is built), the table would include a row with scheduled_year = 2008, grid_id = 23, and residential_units = 200.

The value in the ``improvement_value'' fields, below, are used to indicate how to change the associated improvement_value for this grid cell. Each event will add (improvement_value * (number of units [or sqft] being built by this event)) to the current improvement value in this grid cell. The units of the improvement is currency value, e.g. dollars.

Column Name Data Type Description
grid_id integer Grid cell where the event takes place
scheduled_year short Year where the event will be implemented
starting_development_type_id integer (optional) This field is ignored. It is here so that the schema is the same for the development_events_exogenous and verb|development_event_history| tables.
ending_development_type_id integer This grid cell's development type at the ending of the scheduled_year. Index into the development_types table
residential_units integer  
commercial_sqft integer  
industrial_sqft integer  
governmental_sqft integer  
residential_improvement_value integer See description, above
commercial_improvement_value integer See description, above
industrial_improvement_value integer See description, above
governmental_improvement_value integer See description, above
fraction_residential_land_value float Fraction of residential land in this cell


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Next: The development_event_history table Up: Database Tables about Events Previous: Database Tables about Events   Index
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