MySQL Alter table causes Error: Invalid use of NULL value

Question

My existing table:

+-----------------+---------------+------+-----+---------+-------------------+
| Field           | Type          | Null | Key | Default |          


        

Answer 1

It looks like there are few rows with NULL value.Update all null values to a default date in that column and then try to do a alter.

Try this

--update null value rows
UPDATE enterprise
SET creation_date = CURRENT_TIMESTAMP
WHERE creation_date IS NULL;


ALTER TABLE enterprise 
MODIFY creation_date TIMESTAMP NOT NULL 
DEFAULT CURRENT_TIMESTAMP;

Answer 2

truncate table and alter table to column NOT NULL

Answer 3

You can't use this query until you have NO NULL values in the creation_date column.

Update your creation_date column with some default date and then alter the table.

Like this

UPDATE enterprise SET creation_date = CURRENT_TIMESTAMP WHERE creation_date IS NULL;

ALTER TABLE enterprise MODIFY creation_date TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP;