timezone - Using current time in UTC as default value in PostgreSQL

Question

I have a column of the TIMESTAMP WITHOUT TIME ZONE type and would like to have that default to the current time in UTC. Getting the current time in UTC is easy:

postgres=# select now() at time zone 'utc';
          timezone          
----------------------------
 2013-05-17 12:52:51.337466
(1 row)

As is using the current timestamp for a column:

postgres=# create temporary table test(id int, ts timestamp without time zone default current_timestamp);
CREATE TABLE
postgres=# insert into test values (1) returning ts;
             ts             
----------------------------
 2013-05-17 14:54:33.072725
(1 row)

But that uses local time. Trying to force that to UTC results in a syntax error:

postgres=# create temporary table test(id int, ts timestamp without time zone default now() at time zone 'utc');
ERROR:  syntax error at or near "at"
LINE 1: ...int, ts timestamp without time zone default now() at time zo...

Answer 1

A function is not even needed. Just put parentheses around the default expression:

create temporary table test(
    id int, 
    ts timestamp without time zone default (now() at time zone 'utc')
);