-- https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_unix-timestamp
SELECT UNIX_TIMESTAMP('2015-11-13 10:20:19');
-- -> 1447431619

-- https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_from-unixtime
SELECT FROM_UNIXTIME(1447430881, '%Y-%m-%d %H:%i:%s');
-- -> '2015-11-13 10:08:01'