MySQL query to make date column NULL?
To make a date column null, use ALTER TABLE and MODIFY and set the date to NULL. Following is the syntax −
alter table yourTableName modify column yourColumnName date NULL;
First let us create a table. Here, we set the column to NOT NULL −
mysql> create table DemoTable ( ShippingDate date NOT NULL ); Query OK, 0 rows affected (0.78 sec)
Now, insert NULL value in the above table. An error would generate since we have set the column to be NOT NULL −
mysql> insert into DemoTable values(null); ERROR 1048 (23000) − Column 'ShippingDate' cannot be null
Now, let us alter the table and allow NULL in the above table −
mysql> alter table DemoTable modify column ShippingDate date NULL; Query OK, 0 rows affected (1.81 sec) Records : 0 Duplicates : 0 Warnings : 0
Now, try inserting NULL into the above table using the insert command again. Since we have modified the table to accept NULL, no error will be generated −
mysql> insert into DemoTable values(null); Query OK, 1 row affected (1.21 sec
Display all records from the table using select statement −
mysql> select *from DemoTable;
This will produce the following output −
+--------------+ | ShippingDate | +--------------+ | NULL | +--------------+ 1 row in set (0.00 sec)
The above is the detailed content of MySQL query to make date column NULL?. For more information, please follow other related articles on the PHP Chinese website!
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