Adding timestamp on record update and insert

We are going to run the alter table command and use timestamp as the data type. For the sake of simplicity, I use created_at and update_at column names. The first one is for when the record was created and the second one for when the record was last updated.

When a fresh record is inserted, both the values are going to be same as, current_timestamp is the time when record was inserted as well as updated. When update will run, only update_at value will be updated.

Adding created_at column.

ALTER TABLE table_name
ADD COLUMN created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP;

Adding update_at column.

ALTER TABLE table_name
ADD COLUMN update_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP;

You can create both the fields at the same time too.

ALTER TABLE table_name
ADD COLUMN created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
ADD COLUMN update_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP;