PostgreSQL compare a timestamp with timezone with a timestamp How do you compare a timestamp with a timezone with a timestamp in postgresql?
I am trying to cast one of the 2 to the type of the other but it does not work for me. Eg.

Having 

TS1: 2019-01-07 21:43:00


and

TS2: 2019-01-07 20:43:37+01


I need to compare them and check if they are the same not including the seconds. So I have tried with:

select attimestamp, attimestamp_tz, attimestam=attimestamp_tz::timestamp from attendance where atid=1070


but this will always return false.
create table test (ts1 timestamp without time zone, ts2 timestamp with time zone)



✓






insert into test (ts1, ts2) 
VALUES ('2019-01-07 21:43:00', '2019-01-07 20:43:37+01'), 
       ('2019-01-07 21:43:00', '2019-01-07 20:43:37-01')



2 rows affected






select *, 
       to_char(ts1, 'YYYYMMDDHH24MI') str_ts1, 
       to_char(ts2, 'YYYYMMDDHH24MI') str_ts2, 
       to_char(ts1, 'YYYYMMDDHH24MI') = to_char(ts2, 'YYYYMMDDHH24MI') compare 
from test



ts1                 | ts2                    | str_ts1      | str_ts2      | compare
:------------------ | :--------------------- | :----------- | :----------- | :------
2019-01-07 21:43:00 | 2019-01-07 19:43:37+00 | 201901072143 | 201901071943 | f      
2019-01-07 21:43:00 | 2019-01-07 21:43:37+00 | 201901072143 | 201901072143 | t      



db&lt;>fiddle here