Postgres 9.6

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select version();


version


PostgreSQL 9.6.18 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 8.3.1 20191121 (Red Hat 8.3.1-5), 64-bit


CREATE TABLE modes
(
    user_id integer NOT NULL,
    trip_id int,
    start_time timestamp with time zone NOT NULL,
    end_time timestamp with time zone NOT NULL,
    travelmode text ,
    PRIMARY KEY (user_id, start_time, end_time)
)
INSERT INTO modes (user_id, trip_id, start_time, end_time, travelmode)
VALUES (10,1000,'2008-06-18 13:28:18+01','2008-06-18 13:32:20+01','bus'),
      (10,1001,'2008-06-18 14:47:35+01','2008-06-18 15:05:31+01','bus'),
      (10,1002,'2008-08-01 02:51:47+01','2008-08-01 03:37:43+01','metro'),
      (10,1003,'2008-08-01 03:59:36+01','2008-08-01 04:30:20+01','metro'),
      (10,1004,'2008-08-01 05:20:07+01','2008-08-01 07:03:51+01','car'),
      (10,1005,'2008-08-01 07:17:08+01','2008-08-01 08:06:26+01','bus'),
      (10,1006,'2008-09-15 23:54:20+01','2008-09-16 00:02:44+01','bus'),
      (10,1007,'2008-09-16 00:10:22+01','2008-09-16 00:28:29+01','bus'),
      (10,1008,'2008-09-16 00:58:43+01','2008-09-16 01:07:14+01','metro')
9 rows affected

SELECT * FROM modes


user_id
trip_id
start_time
end_time
travelmode


10
1000
2008-06-18 13:28:18+01
2008-06-18 13:32:20+01
bus

10
1001
2008-06-18 14:47:35+01
2008-06-18 15:05:31+01
bus

10
1002
2008-08-01 02:51:47+01
2008-08-01 03:37:43+01
metro

10
1003
2008-08-01 03:59:36+01
2008-08-01 04:30:20+01
metro

10
1004
2008-08-01 05:20:07+01
2008-08-01 07:03:51+01
car

10
1005
2008-08-01 07:17:08+01
2008-08-01 08:06:26+01
bus

10
1006
2008-09-15 23:54:20+01
2008-09-16 00:02:44+01
bus

10
1007
2008-09-16 00:10:22+01
2008-09-16 00:28:29+01
bus

10
1008
2008-09-16 00:58:43+01
2008-09-16 01:07:14+01
metro


CREATE TABLE plt_distinct
(
    user_id int,
    trip_id int, 
    logtime timestamp with time zone NOT NULL,
    lat double precision NOT NULL,
    lon double precision NOT NULL,
    alt double precision,
    PRIMARY KEY (trip_id, logtime)
)
INSERT INTO plt_distinct (user_id, trip_id, logtime, lat, lon, alt)
VALUES (10,1002,'2008-06-18 04:46:20+01',39.940474,116.346754,233),
      (10,1002,'2008-06-18 04:46:21+01',39.940491,116.346745,233),
      (10,1002,'2008-06-18 04:46:23+01',39.940526,116.346734,233),
      (10,1002,'2008-06-18 04:46:25+01',39.940573,116.346725,233),
      (10,1002,'2008-06-18 04:46:31+01',39.940815,116.346688,230),
      (10,1002,'2008-06-18 04:46:32+01',39.940861,116.346661,230),
      (10,1002,'2008-06-18 04:46:33+01',39.940941,116.346599,233),
      (10,1002,'2008-06-18 04:46:35+01',39.941109,116.34658,233),
      (10,1002,'2008-06-18 04:46:39+01',39.941464,116.346561,240),
      (10,1002,'2008-06-18 04:46:40+01',39.941558,116.346521,246),
      (10,1002,'2008-06-18 04:46:42+01',39.941816,116.346438,259)
11 rows affected

SELECT * FROM plt_distinct


user_id
trip_id
logtime
lat
lon
alt


10
1002
2008-06-18 04:46:20+01
39.940474
116.346754
233

10
1002
2008-06-18 04:46:21+01
39.940491
116.346745
233

10
1002
2008-06-18 04:46:23+01
39.940526
116.346734
233

10
1002
2008-06-18 04:46:25+01
39.940573
116.346725
233

10
1002
2008-06-18 04:46:31+01
39.940815
116.346688
230

10
1002
2008-06-18 04:46:32+01
39.940861
116.346661
230

10
1002
2008-06-18 04:46:33+01
39.940941
116.346599
233

10
1002
2008-06-18 04:46:35+01
39.941109
116.34658
233

10
1002
2008-06-18 04:46:39+01
39.941464
116.346561
240

10
1002
2008-06-18 04:46:40+01
39.941558
116.346521
246

10
1002
2008-06-18 04:46:42+01
39.941816
116.346438
259

user_id	trip_id	start_time	end_time	travelmode
10	1000	2008-06-18 13:28:18+01	2008-06-18 13:32:20+01	bus
10	1001	2008-06-18 14:47:35+01	2008-06-18 15:05:31+01	bus
10	1002	2008-08-01 02:51:47+01	2008-08-01 03:37:43+01	metro
10	1003	2008-08-01 03:59:36+01	2008-08-01 04:30:20+01	metro
10	1004	2008-08-01 05:20:07+01	2008-08-01 07:03:51+01	car
10	1005	2008-08-01 07:17:08+01	2008-08-01 08:06:26+01	bus
10	1006	2008-09-15 23:54:20+01	2008-09-16 00:02:44+01	bus
10	1007	2008-09-16 00:10:22+01	2008-09-16 00:28:29+01	bus
10	1008	2008-09-16 00:58:43+01	2008-09-16 01:07:14+01	metro

user_id	trip_id	logtime	lat	lon	alt
10	1002	2008-06-18 04:46:20+01	39.940474	116.346754	233
10	1002	2008-06-18 04:46:21+01	39.940491	116.346745	233
10	1002	2008-06-18 04:46:23+01	39.940526	116.346734	233
10	1002	2008-06-18 04:46:25+01	39.940573	116.346725	233
10	1002	2008-06-18 04:46:31+01	39.940815	116.346688	230
10	1002	2008-06-18 04:46:32+01	39.940861	116.346661	230
10	1002	2008-06-18 04:46:33+01	39.940941	116.346599	233
10	1002	2008-06-18 04:46:35+01	39.941109	116.34658	233
10	1002	2008-06-18 04:46:39+01	39.941464	116.346561	240
10	1002	2008-06-18 04:46:40+01	39.941558	116.346521	246
10	1002	2008-06-18 04:46:42+01	39.941816	116.346438	259