[SOLVED] Postgres AT TIME ZONE function shows wrong time?

Postgres AT TIME ZONE function shows wrong time?

I am using transformation to new timezone UTC+3 which is equal to EAT timezone, but Postgres (9.1) shows the wrong time

select '2015-01-13 08:40:00.0'::timestamp with time zone AT TIME ZONE 'UTC+03', 
       '2015-01-13 08:40:00.0'::timestamp with time zone AT TIME ZONE 'EAT';

(default timezone is Stockholm here)

The result is

"2015-01-13 04:40:00",
"2015-01-13 10:40:00"

Why?

it should be 2015-01-13 10:40:00

if using JodaTime with both timezones then it shows the same correct result '2015-01-13 10:40:00'.

Solution

A time zone name spelled like 'UTC+3:00' is a POSIX time zone specification. In this style, zones west of GMT have a positive sign and those east have a negative sign in their name (e.g "Etc/GMT-14" is 14 hours ahead/east of GMT.)

See http://www.postgresql.org/docs/9.3/static/datatype-datetime.html#DATATYPE-TIMEZONES