Here is the MySQL function to use to get the current datetime as ISO 8601 format as asked in DarwinCore:
DATE_FORMAT() is obviously a function for formatting date and time, and we are using here
%Y for four-digit year,
%m for two-digits month,
%d for two-digits day and
%T for 24-hour time (hh:mm:ss).
NOW() gives the current datetime.
And then you get a nice figure like this one:
Note that the same result can be achieved with:
CONCAT() is used for concatenating strings, and
CURTIME() give respectively the current date and the current time.
UPDATE: There is now a page for getting the current datetime in different formats. Check the page here: Get the current date in different formats in MySQL.