CONVERT_TZ() converts a datetime value dt from the time zone given by from_tz to the time zone given by to_tz and returns the resulting value.
In order to use named time zones, such as GMT, MET or Africa/Johannesburg, the time_zone tables must be loaded (see mysql_tzinfo_to_sql).
No conversion will take place if the value falls outside of the supported TIMESTAMP range ('1970-01-01 00:00:01' to '2038-01-19 05:14:07' UTC) when converted from from_tz to UTC.
This function returns NULL if the arguments are invalid (or named time zones have not been loaded).