The mysql time field is set to the current time by default

1. Add the column directly when creating the table and declare the default value, as follows:

CREATE TABLE `table1` (
`id` int(11) NOT NULL,
`createtime` timestamp NULL default CURRENT_TIMESTAMP,
`updatetime` timestamp NULL default CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

If you are operating under navicat, set the field type to timestamp, and write the default value to CURRENT_TIMESTAMP, as shown below:

2. 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 a default value

alter table table1
change createtime newtime timestamp null default current_timestamp

4, display milliseconds

If you want to record to milliseconds, set CURRENT_TIMESTAMP(3)

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