I'm working with GTFS structure for the first time and am having trouble with the queries. I've got the transit data into mysql tables, and am free to query them, but I feel like I'm doing far too many queries and for loops to get the simplest info.
What I'd like to get in a single query is all the departure times and arrival times between two known stops, possibly identified by name.
Here is what I have so far, which involves a query, followed by looping through each trip_id to find the departure and arrival station info + times.
Query 1:
Show all departure times from a particular origin station, going in a particular direction. Result will give departure times and trip_ids.
SELECT t.trip_id, trip_headsign, departure_time, direction_id, s.stop_name
FROM stops s, routes r, stop_times st, calendar c, trips t
WHERE departure_time > "00:00:00" and departure_time < "23:59:59"
AND r.route_id=1 and s.stop_id = 42
AND s.stop_id = st.stop_id
AND st.trip_id = t.trip_id
AND c.service_id = t.service_id
AND c.monday=1 and direction_id=1;
Result
+---------+---------------+----------------+--------------+-----------+
| trip_id | trip_headsign | departure_time | direction_id | stop_name |
+---------+---------------+----------------+--------------+-----------+
| 5671498 | Grand Central | 04:43:00 | 1 | Garrison |
| 5671501 | Grand Central | 05:13:00 | 1 | Garrison |
| 5671504 | Grand Central | 05:43:00 | 1 | Garrison |
| 5671506 | Grand Central | 06:08:00 | 1 | Garrison |
| 5671507 | Grand Central | 06:32:00 | 1 | Garrison |
| 5671513 | Grand Central | 06:53:00 | 1 | Garrison |
| 5671516 | Grand Central | 07:18:00 | 1 | Garrison |
| 5671519 | Grand Central | 07:40:00 | 1 | Garrison |
| 5671521 | Grand Central | 08:03:00 | 1 | Garrison |
| 5671523 | Grand Central | 08:32:00 | 1 | Garrison |
| 5671525 | Grand Central | 08:58:00 | 1 | Garrison |
| 5671526 | Grand Central | 09:27:00 | 1 | Garrison |
| 5671529 | Grand Central | 10:24:00 | 1 | Garrison |
| 5671532 | Grand Central | 11:24:00 | 1 | Garrison |
| 5671535 | Grand Central | 12:24:00 | 1 | Garrison |
| 5671537 | Grand Central | 13:24:00 | 1 | Garrison |
| 5671540 | Grand Central | 14:24:00 | 1 | Garrison |
| 5671542 | Grand Central | 15:24:00 | 1 | Garrison |
| 5671543 | Grand Central | 16:22:00 | 1 | Garrison |
| 5671547 | Grand Central | 17:24:00 | 1 | Garrison |
| 5671550 | Grand Central | 18:24:00 | 1 | Garrison |
| 5671552 | Grand Central | 19:26:00 | 1 | Garrison |
| 5671554 | Grand Central | 20:24:00 | 1 | Garrison |
| 5671556 | Grand Central | 21:24:00 | 1 | Garrison |
| 5671557 | Grand Central | 22:24:00 | 1 | Garrison |
| 5671559 | Croton-Harmon | 23:24:00 | 1 | Garrison |
+---------+---------------+----------------+--------------+-----------+
Query 2:
Give me all the stops on a particular trip along with their arrival times, use trip_id from last query:
SELECT s.stop_id,stop_lat, stop_lon, stop_name, arrival_time, stop_sequence
FROM stop_times st JOIN stops s ON s.stop_id=st.stop_id
WHERE trip_id=5671521;
Result
+---------+-----------+------------+------------------+--------------+---------------+
| stop_id | stop_lat | stop_lon | stop_name | arrival_time | stop_sequence |
+---------+-----------+------------+------------------+--------------+---------------+
| 51 | 41.705839 | -73.937946 | Poughkeepsie | 07:31:00 | 1 |
| 49 | 41.587448 | -73.947226 | New Hamburg | 07:41:00 | 2 |
| 46 | 41.504007 | -73.984528 | Beacon | 07:50:00 | 3 |
| 43 | 41.415283 | -73.958090 | Cold Spring | 07:58:00 | 4 |
| 42 | 41.381780 | -73.947202 | Garrison | 08:03:00 | 5 |
| 40 | 41.332601 | -73.970426 | Manitou | 08:08:00 | 6 |
| 39 | 41.285962 | -73.930420 | Peekskill | 08:17:00 | 7 |
| 37 | 41.246259 | -73.921884 | Cortlandt | 08:22:00 | 8 |
| 33 | 41.189903 | -73.882394 | Croton-Harmon | 08:32:00 | 9 |
| 4 | 40.805157 | -73.939149 | Harlem-125th St. | 09:09:00 | 10 |
| 1 | 40.752998 | -73.977056 | Grand Central | 09:22:00 | 11 |
+---------+-----------+------------+------------------+--------------+---------------+
What I'd really like is a list of departure times and arrival times between two stops, such as this theorized result:
+---------+----------------+----------------+-----------+---------------+--------------+
| trip_id | departure_stop | departure_time | direction | arrival_stop | arrival_time |
+---------+----------------+----------------+-----------+---------------+--------------+
| 5671521 | Garrison | 08:03:00 | 1 | Grand Central | 09:22:00 |
| 5671522 | Garrison | 08:32:00 | 1 | Grand Central | 09:51:00 |
...etc...
simply joining data together, joining to stops twice for start and end stop and joining to stop_times twice for start and end stop_times,
the only thing i am unsure about is where direction_id comes from.
try the below query.
At the very end of the query, you can specify start_s.stop_id and end_s.stop_id which represents the two stops you're querying data about.
SELECT t.trip_id,
start_s.stop_name as departure_stop,
start_st.departure_time,
direction_id as direction,
end_s.stop_name as arrival_stop,
end_st.arrival_time
FROM
trips t INNER JOIN calendar c ON t.service_id = c.service_id
INNER JOIN routes r ON t.route_id = r.route_id
INNER JOIN stop_times start_st ON t.trip_id = start_st.trip_id
INNER JOIN stops start_s ON start_st.stop_id = start_s.stop_id
INNER JOIN stop_times end_st ON t.trip_id = end_st.trip_id
INNER JOIN stops end_s ON end_st.stop_id = end_s.stop_id
WHERE c.monday = 1
AND direction_id = 1
AND start_st.departure_time > "00:00:00" AND start_st.departure_time < "23:59:59"
AND r.route_id = 1
AND start_s.stop_id = 42
AND end_s.stop_id = 1
I tried looking up GTFS structure example from this link and i couldn't find anything on direction_id
To specify stop names instead of AND start_s.stop_id = 42 AND end_s.stop_id = 1
just use AND start_s.stop_name = 'Garrison' AND end_s.stop_name = 'Grand Central'
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