Mysql> create a table by adding this column and stating default values as follows:
CREATE TABLE `table1` ( `id` int(11) NOT NULL, `createtime` timestamp NULL default CURRENT_TIMESTAMP ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
If you are operating under Navicat, set the field type to TIMESTAMP, and write CURRENT_TIMESTAMP as the default value, as shown below:
Add a new column to an existing table
ALTER TABLE table1 ADD COLUMN `createtime` timestamp NULL DEFAULT CURRENT_TIMESTAMP
3. Modify the time format of a column and add the default value
alter table table1 change createtime newtime timestamp null default current_timestamp