create table tz_test ( comment varchar, ts timestamp, ts_tz timestamptz );
insert into tz_test (comment, ts, ts_tz) values ( 'in "local"', TIMESTAMP WITH TIME ZONE '2003-04-12 04:05:06 America/New_York', TIMESTAMP WITH TIME zone '2003-04-12 04:05:06 America/New_York'), ( 'flattened to UTC', (TIMESTAMP WITH TIME ZONE '2003-04-12 04:05:06 America/New_York') at time zone 'UTC', TIMESTAMP WITH TIME zone '2003-04-12 04:05:06 America/New_York'), ( 'in "local" no types', TIMESTAMP WITH TIME ZONE '2003-04-12 04:05:06 America/New_York', '2003-04-12 04:05:06 America/New_York'), ( 'flattened to UTC no types', (TIMESTAMP WITH TIME ZONE '2003-04-12 04:05:06 America/New_York') at time zone 'UTC', '2003-04-12 04:05:06 America/New_York');
select comment, ts, ts AT TIME ZONE 'UTC' as ts_utc, ts_tz, ts_tz AT TIME ZONE 'UTC' as ts_tz_utc, case when ts < ts_tz then 'less' when ts>ts_tz then 'greater' else 'equal' end from tz_test;