location table structure

The Location table holds all the activity and household locations in the model, on which all trips will ultimately start and end.

Given its central importance in the model, this table is connected to multiple other tables, both through data links and geographic ones.

Required by all models.

Table Structure

Field	Type	NULL allowed	Default Value	Foreign key	Description
location*	INTEGER	NO			Unique ID referencing a particular location in the model
link	INTEGER	NO			Foreign key reference to one link that is the closest spatially to the location
dir	INTEGER	NO	0		The direction of the link (ab or ba) that is closest to the location. Can be used to infer which side of the link this location may lie (but not trivial).
offset	REAL	NO	0		Auto-generated value of how far from the location (perpendicular) the link is present.
setback	REAL	NO	0		Auto-generated value of how far from node_a of the link this location is present along the length of the link
zone	INTEGER	YES			Foreign key reference to the zone where this location in situated. Auto-generated through geo-consistency checks.
x	REAL	NO	0		Auto-generated value of the x coordinate of the location specified in meters (UTM transform)
y	REAL	NO	0		Auto-generated value of the y coordinate of the location specified in meters (UTM transform)
area_type	INTEGER	NO	0		Foreign-key reference to Area_Type to define the general characteristic of the area where the location is situated. It is necessarily the same as the zone where the location is situated
lu_area	REAL	NO	0		The area (in ???) of the same land use aggregated around the location
notes	TEXT	YES	“”		Text area to specify notes about the location. Optional.
census_zone	REAL	NO	0		FIPS code representing the census tract that this location is contained within. Census tract FIPS code is 11-digit long.
land_use	TEXT	NO	“ALL”	Land_Use(land_use)	Text describing the land use type represented by this location. Values at land_use.
walk_link	INTEGER	YES			Foreign key reference to the nearest walk link from the Transit_Walk table
walk_offset	REAL	YES			Same as offset above, but for the walk link.
bike_link	INTEGER	YES			Foreign key reference to the nearest bike link from the Transit_Bike table
bike_offset	REAL	YES			Same as offset above, but for the bike link.
avg_parking_cost	REAL	YES	0		Average parking cost when visiting the location. Used in the activity planning stage.
res_charging	REAL	YES			Denotes the proportion of households at this location that have residential charging available.
stop_flag	INTEGER	YES	0		Boolean to denote whether or not a location is a TNC stop, primarily for aggregated pickups and drop-offs. May be deprecated.
tod_distance	REAL	NO	0		Walk distance to the closest high-quality transit stop, in meters. The definition of “high quality” is user dependent and can be calculated using the DistanceToTransit class from Polaris-Studio.
geo	POINT	NO	‘’

(* - Primary key)

The SQL statement for table and index creation is below.

create TABLE IF NOT EXISTS "Location" (
    "location"         INTEGER NOT NULL PRIMARY KEY,
    "link"             INTEGER NOT NULL,
    "dir"              INTEGER NOT NULL DEFAULT 0,
    "offset"           REAL    NOT NULL DEFAULT 0,
    "setback"          REAL    NOT NULL DEFAULT 0,
    "zone"             INTEGER,
    "x"                REAL    NOT NULL DEFAULT 0,
    "y"                REAL    NOT NULL DEFAULT 0,
    "area_type"        INTEGER NOT NULL DEFAULT 0,
    "lu_area"          REAL    NOT NULL DEFAULT 0,
    "notes"            TEXT             DEFAULT "",
    "census_zone"      REAL    NOT NULL DEFAULT 0,
    "land_use"         TEXT    NOT NULL DEFAULT "ALL",
    "walk_link"        INTEGER,
    "walk_offset"      REAL,
    "bike_link"        INTEGER,
    "bike_offset"      REAL,
    "avg_parking_cost" REAL             DEFAULT 0,
    "res_charging"     REAL,
    "stop_flag"        INTEGER          DEFAULT 0,
    "tod_distance"     REAL    NOT NULL DEFAULT 0,

    CONSTRAINT "land_use_fk" FOREIGN KEY("land_use") REFERENCES "Land_Use"("land_use") DEFERRABLE INITIALLY DEFERRED
);

select AddGeometryColumn( 'Location', 'geo', SRID_PARAMETER, 'POINT', 'XY', 1 );
select CreateSpatialIndex( 'Location' , 'geo');

create INDEX IF NOT EXISTS "notes_idx" ON "Location" ("notes");
create INDEX IF NOT EXISTS "loc_zone" ON "Location" ("zone");
create INDEX IF NOT EXISTS "location_idx" ON "Location" ("location");

Enums

The following enums are used in this table.

land_use

Enum Values

Value	Description
0	LU_AGRICULTURE
1	LU_ALL
2	LU_BUSINESS
3	LU_CIVIC_RELIGIOUS
4	LU_CULTURAL
5	LU_DISTRIBUTION
6	LU_INTERMODAL
7	LU_EDUCATION
8	LU_HIGHER_EDUCATION
9	LU_HOTEL
10	LU_INDUSTRIAL
11	LU_MANUFACTURING
12	LU_SHOPPING
13	LU_MEDICAL
14	LU_MIXED_USE
15	LU_NONE
16	LU_NON_RESIDENTIAL
17	LU_RESIDENTIAL
18	LU_RESIDENTIAL_MULTI
19	LU_RECREATION
20	LU_SPECIAL_GENERATOR
21	TRANSIT_STOP
22	LU_SERVICE
23	LU_RETAIL
24	LU_RESTAURANT
25	LU_EXTERNAL