SELECT past hour data - postgresql

Question

I have a simple database
id name value date time
1 box 34 2020-06-08 14:45:00
2 box 35 2020-06-08 15:00:00
3 box 4 2020-06-08 15:15:00
4 box 44 2020-06-08 15:30:00
5 box 42 2020-06-08 15:45:00
6 box 41 2020-06-08 16:00:00
7 box 0 2020-06-08 16:15:00
8 box 0 2020-06-08 16:30:00
9 box 0 2020-06-08 16:45:00
...
I am trying to retrieve the latest past 1 hour data from a Postgresql database. The objective is to run this query every hour to get the past one hour data for further processing in another software.
The records in the database already contain all the timestamps for the day (15 minutes interval).
Therefore, from the example, assuming my local time is 16:00:00, I will want to take the past 1 hour data from my local time.
I have tried the following:
SELECT id, name, value, date, time
FROM boxbox
WHERE time >= (NOW() - INTERVAL '1 hour')
ORDER BY time desc
But I am getting this SQL error
SQL Error [42883]: ERROR: operator does not exist: time without time zone >=
timestamp with time zone
The table datatype is as follow:
id - int4
name - varchar
value - int
date - date
time - time
Thank you.

Answer 1

Well, now() returns a timestamp with time zone, not a time value. And you can't compare a time value with a timestamp with time zone value.
You need to use localtime:
SELECT id, name, value, "date", "time"
FROM boxbox
WHERE "time" >= localtime - INTERVAL '1 hour'
ORDER BY "time" desc
However the above won't work properly if the time crossed midnight. If you also need to take care of that, you need to combine your date and time columns to a single timestamp column:
SELECT id, name, value, "date", "time"
FROM boxbox
WHERE "date" + "time" >= now () - INTERVAL '1 hour'
ORDER BY "time" desc