The MariaDB database was found 12 hours late

One   Problem description

The current time is 2022 year 6 month 27 Japan 11:32, But I checked the current time in the database later than now 12 Hours ：

SELECT NOW();

2022-06-26 23:30:51

Found that the time zone is the U.S. time zone （EDT）, Non Chinese time zone ：

  Two Investigation thought

Look at the time zone of the operating system ( perform date command ), If the time zone of the operating system is incorrect , The time zone in the database will not be correct .

The operating system time zone needs to be modified （ Please refer to linux CST And EDT Time zone interchange _ Yabingshi's blog -CSDN Blog ）, Then restart the database .

If you don't want to restart the online database , You can also execute commands ：

SET  global time_zone = '+8:00';

It's just set The command only takes effect for new connections , Will not change the existing connection .
So the previous connection or the previous time , I suggest restarting the database at night （ no need set global, Just restart the database directly ）