transit trips table structure

The Transit_Trips table holds the complete list of all transit services operating, for which one can override the information on capacity coming from route/pattern. There is also information on whether the vehicle is articulated or if it has multiple cars (applicable to rail), but both of these fields default to 0 in case of regular bus services.

The transit trip ID can be traced back to the pattern, route and agency directly through the encoding of their trip_id, as explained in the documentation for the Transit_Agencies table.

Many fields are not used during POLARIS simulation, and are stored only so a GTFS export after editing remains consistent with the GTFS originally imported. These fields are marked with “Not used by POLARIS” in the comments below.

Table Structure

Field	Type	NULL allowed	Default Value	Foreign key	Description
trip_id*	INTEGER	NO			ID of the individual trip in the format AARRRRPPPPTTTT (Agency, Route, Pattern, Trip)
trip	TEXT	YES			Trip identifier as shown in the GTFS feed
dir	INTEGER	NO			Direction of the trip
pattern_id	BIGINT	NO		Transit_Patterns(pattern_id)	ID of the pattern this trip refers to
seated_capacity	INTEGER	YES	NULL		Seated capacity of the vehicles operating this trip. Overrides the information on the transit_patterns table
design_capacity	INTEGER	YES	NULL		Design capacity of the vehicles operating this trip. Overrides the information on the transit_patterns table
total_capacity	INTEGER	YES	NULL		Total capacity of the vehicles operating this trip, actually used in POLARIS as opposed to design_capacity. Overrides the information on the transit_patterns table
is_artic	INTEGER	YES	0		Whether the vehicle is articulated or not. 1 for articulated, 0 for non-articulated. Used to calculate bus capacities, not directly used in POLARIS
number_of_cars	INTEGER	YES	0		Number of train cars operating this trip. 0 for regular bus services. Used to calculate the train capacities, not directly used in POLARIS
headsign	TEXT	YES			trips.txt trip_headsign: text shown to riders for the trip’s destination. Not used by POLARIS
short_name	TEXT	YES			trips.txt trip_short_name: short rider-facing name for the trip. Not used by POLARIS
block_id	TEXT	YES			trips.txt block_id: identifier for blocks of trips operated by the same vehicle. Not used by POLARIS
wheelchair_accessible	INTEGER	YES	0		trips.txt wheelchair_accessible: 0 unknown, 1 accessible, 2 not accessible. Not used by POLARIS
bikes_allowed	INTEGER	YES	0		trips.txt bikes_allowed: 0 unknown, 1 allowed, 2 not allowed. Not used by POLARIS

(* - Primary key)

The SQL statement for table and index creation is below.

CREATE TABLE IF NOT EXISTS Transit_Trips(
    trip_id               INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
    trip                  TEXT,
    dir                   INTEGER NOT NULL,
    pattern_id            BIGINT  NOT NULL,
    seated_capacity       INTEGER DEFAULT NULL,
    design_capacity       INTEGER DEFAULT NULL,
    total_capacity        INTEGER DEFAULT NULL,
    is_artic              INTEGER DEFAULT 0,
    number_of_cars        INTEGER DEFAULT 0,
    headsign              TEXT,
    short_name            TEXT,
    block_id              TEXT,
    wheelchair_accessible INTEGER DEFAULT 0,
    bikes_allowed         INTEGER DEFAULT 0,
    FOREIGN KEY(pattern_id) REFERENCES Transit_Patterns(pattern_id) deferrable initially deferred
);