Timestamp-type automatic update time when the record is updated in MySQL

In MySQL, when the record is updated, I use navicat for the timestamp type automatic update time. If I select timestamp for the date type, I find that IDE has an option:

View the automatically generated SQL statement by IDE: Write 'lastupdate' timestamp NOT NULL DEFAULT '2017-00-00 00:00:00 'ON UPDATE CURRENT_TIMESTAMP if this option is removed: the difference between 'lastupdate' timestamp not null default '2017-00-00 00:00:00 'Is that "on update CURRENT_TIMESTAMP, its function is to automatically update the lastUpdate time to the current time of the system when the record is changed. Note: The change is emphasized. In other words, this value will not be automatically updated even if the update statement is used but the content does not change.