national ports table structure

national ports table structure#

This table includes the attributes of all ports where international shipment goods exit or enter the modelled city, including the port name, county, geographic information, and annual import and export weights

Table Structure#
Field	Type	NULL allowed	Default Value	Description
national_port*	INTEGER	NO		The unique identifier of the port
name	TEXT	NO		Name of the port, as commonly known
county	INTEGER	NO	0	The county FIPS code of the port
x	NUMERIC	NO	0	x coordinate of the port. Automatically added by Polaris
y	NUMERIC	NO	0	y coordinate of the port. Automatically added by Polaris
imports	NUMERIC	NO	0	Annual import weights of the port (units: metric tons)
exports	NUMERIC	NO	0	Annual export weights of the port (units: metric tons)

(* - Primary key)

The SQL statement for table and index creation is below.

CREATE TABLE National_Ports (
    "national_port"       INTEGER NOT NULL  PRIMARY KEY,
    "name"                TEXT    NOT NULL,
    "county"              INTEGER NOT NULL DEFAULT 0,
    "x"                   NUMERIC NOT NULL DEFAULT 0,
    "y"                   NUMERIC NOT NULL DEFAULT 0,
    "imports"             NUMERIC NOT NULL DEFAULT 0,
    "exports"             NUMERIC NOT NULL DEFAULT 0
);
SELECT AddGeometryColumn( 'National_Ports', 'geo', SRID_PARAMETER, 'POINT', 'XY', 1);
SELECT CreateSpatialIndex( 'National_Ports' , 'geo' );
CREATE INDEX IF NOT EXISTS "NATIONAL_PORT_I" ON "National_Ports" ("national_port");