The development_constraints table

This table defines rules that restrict the possible development types a developer can create on a particular grid cell. Each row defines one rule. Development is not allowed on any gridcell that matches any of these rules. A gridcell matches a rule if the attribute values for the gridcell match all of the values in the rule (rule columns with the value ``-1'' are ignored when determining a match).

Column Name	Data Type	Description
constraint_id	integer	Unique rule identification number
name-of-a-gridcell-attribute	integer or float	Value for this attribute, or ``-1'' if this attribute is not part of the constraint (e.g. don't care)
min_units	integer	Minimum number of residential units for a gridcell. A development project may only be placed on this gridcell if it will result in this gridcell containing at least this number of residential units.
max_units	integer	Maximum number of residential units for a gridcell. A development project may only be placed on this gridcell if it will result in this gridcell containing at most this number of residential units.
min_commercial_sqft	integer	Minimum number of commercial sqft. for a gridcell. A development project may only be placed on this gridcell if it will result in this gridcell containing at least this number of commercial sqft.
max_commercial_sqft	integer	Maximum number of commercial sqft. for a gridcell. A development project may only be placed on this gridcell if it will result in this gridcell containing at most this number of commercial sqft.
min_industrial_sqft	integer	Minimum number of industrial sqft. for a gridcell. A development project may only be placed on this gridcell if it will result in this gridcell containing at least this number of industrial sqft.
max_industrial_sqft	integer	Maximum number of industrial sqft. for a gridcell. A development project may only be placed on this gridcell if it will result in this gridcell containing at most this number of industrial sqft.

• constraint_id must be a unique positive integer.

• name-of-a-gridcell-attribute is the name of a gridcell attribute, e.g. city_id or is_in_wetland. The set of available attribute names is determined by the set of numeric column names on the gridcell table.

• Within each min_/max_ pair, the max must be greater than or equal to the min, e.g., min_units $<=$ max_units.