Can MySQL INT type be non-zero NULL?

You can set the INT column to value NULL.The column INT type a nullable column. The syntax is as follows:

INSERT INTO yourTableName(yourIntColumnName) values(NULL);

To understand the above syntax, let us create a table. The query to create a table is as follows:

mysql> create table nullableIntDemo
   -> (
   -> Id int NOT NULL AUTO_INCREMENT,
   -> Price int,
   -> PRIMARY KEY(Id)
   -> );
Query OK, 0 rows affected (0.80 sec)

Insert the record as NULL for a int column ‘Price’. The query is as follows:

mysql> insert into nullableIntDemo(Price) values(NULL);
Query OK, 1 row affected (0.11 sec)
mysql> insert into nullableIntDemo(Price) values(100);
Query OK, 1 row affected (0.15 sec)
mysql> insert into nullableIntDemo(Price) values(200);
Query OK, 1 row affected (0.12 sec)
mysql> insert into nullableIntDemo(Price) values(NULL);
Query OK, 1 row affected (0.13 sec)
mysql> insert into nullableIntDemo(Price) values(NULL);
Query OK, 1 row affected (0.10 sec)

Display all records from the table using select statement. The query is as follows:

mysql> select *from nullableIntDemo;

The following is the output:

+----+-------+
| Id | Price |
+----+-------+
|  1 | NULL  |
|  2 | 100   |
|  3 | 200   |
|  4 | NULL  |
|  5 | NULL  |
+----+-------+
5 rows in set (0.00 sec)

Look at the above sample output, in MySQL int column is a nullable.