33

How do I set a timestamp column whose default value is the current UTC time?

MySQL uses UTC_TIMESTAMP() function for UTC timestamp:

mysql> SELECT UTC_TIMESTAMP();
+---------------------+
| UTC_TIMESTAMP()     |
+---------------------+
| 2012-07-01 11:36:35 |
+---------------------+
1 row in set (0.00 sec)

So I've tried:

CREATE TABLE `blah` (
`creation_time` TIMESTAMP DEFAULT UTC_TIMESTAMP,
...

And other variations, like UTC_TIMESTAMP(), but without success.

  • Did you try CURRENT_TIMESTAMP ? – ypercubeᵀᴹ Jul 1 '12 at 11:36
  • 1
    It works, but it does not store the a local timezone value instead of UTC. – Adam Matan Jul 1 '12 at 11:40
  • What exactly do you want to do? Store in the table column the UTC timestamp? Or something else? – ypercubeᵀᴹ Jul 1 '12 at 11:48
  • 8
    From The DATE, DATETIME, and TIMESTAMP Types: MySQL converts TIMESTAMP values from the current time zone to UTC for storage, and back from UTC to the current time zone for retrieval. – ypercubeᵀᴹ Jul 1 '12 at 12:05
  • 3
    Be aware that the storage as UTC only applies to the TIMESTAMP datatype, not to DATE and DATETIME (although you can set their default to CURRENT_TIMESTAMP). From the same documentation page: (This does not occur for other types such as DATETIME.). – AronVanAmmers Mar 2 '15 at 20:03
46

To go along with @ypercube's comment that CURRENT_TIMESTAMP is stored as UTC but retrieved as the current timezone, you can affect your server's timezone setting with the --default_time_zone option for retrieval. This allows your retrieval to always be in UTC.

By default, the option is 'SYSTEM' which is how your system time zone is set (which may or may not be UTC!):

mysql> SELECT @@global.time_zone, @@session.time_zone;
+--------------------+---------------------+
| @@global.time_zone | @@session.time_zone |
+--------------------+---------------------+
| SYSTEM             | SYSTEM              |
+--------------------+---------------------+
1 row in set (0.00 sec)

mysql> SELECT CURRENT_TIMESTAMP();
+---------------------+
| CURRENT_TIMESTAMP() |
+---------------------+
| 2012-09-25 16:28:45 |
+---------------------+
1 row in set (0.00 sec)

You can set this dynamically:

mysql> SET @@session.time_zone='+00:00';
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT @@global.time_zone, @@session.time_zone;
+--------------------+---------------------+
| @@global.time_zone | @@session.time_zone |
+--------------------+---------------------+
| SYSTEM             | +00:00              |
+--------------------+---------------------+
1 row in set (0.00 sec)

Or permanently in your my.cnf:

[mysqld]
**other variables**
default_time_zone='+00:00'

Restart your server, and you will see the change:

mysql> SELECT @@global.time_zone, @@session.time_zone;
+--------------------+---------------------+
| @@global.time_zone | @@session.time_zone |
+--------------------+---------------------+
| +00:00             | +00:00              |
+--------------------+---------------------+
1 row in set (0.00 sec)

mysql> SELECT CURRENT_TIMESTAMP();
+---------------------+
| CURRENT_TIMESTAMP() |
+---------------------+
| 2012-09-25 20:27:50 |
+---------------------+
1 row in set (0.01 sec)
  • 2
    Very helpful post!! – om39a Jun 2 '14 at 19:44
  • Is it possible to specify default_time_zone for a specific table or database? Thanks. – W.M. Aug 11 '16 at 15:20
  • 2
    Is it possible to specify default_time_zone for a specific query? – mcmillab Aug 22 '16 at 5:06
  • @mcmillab you can set the session timezone prior to running the query, then reset to the global timezone before running further queries (or re-connect). – Derek Downey Aug 22 '16 at 13:39
  • Following on mcmillab -- or to query the column with an operator that shows the underlying UTC value (since conversion isn't 1-to1)? – Marc L. Jun 30 '17 at 15:03
4

You can not specify UTC_TIMESTAMP as default to specify automatic properties, You should use only the DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP clauses.

Also you can INSERT UTC_TIMESTAMP values like this though for a table:

CREATE TABLE `test` (
  `ts` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);

INSERT query would be like this to insert UTC_TImeSTAMP:

insert into `test` (`ts`) 
values
  (utc_timestamp()) ;
  • Thanks for "You can not specify UTC_TIMESTAMP as default to specify automatic properties" – Barbaros Alp Feb 1 '16 at 13:44
3

My solution is with a trigger:

DELIMITER //
CREATE TRIGGER `update_to_utc` BEFORE INSERT ON `my_table` FOR EACH ROW BEGIN
set new.my_field=utc_timestamp();
END//
DELIMITER ;

Then every new inserted row will have the timestamp in UTC.

1

for mariadb only the global my.cnf solutions did work

for mariadb 10.2, the permanent solution of @Derek Downey in this post.

[mysqld]
**other variables**
default_time_zone='+00:00'

for mariadb 10.0 (i had 10.0.32), see https://stackoverflow.com/questions/947299/how-do-i-make-mysqls-now-and-curdate-functions-use-utc

[mysqld_safe]
**other variables**
timezone = UTC

both definitions may coexist in my.cnf of mariadb 10.2, but i don't have mariadb 10.0 anymore.

hope this will help you.

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