How do I insert a NULL value in MySQL?
To insert a NULL value, you can use UPDATE command. Following is the syntax −
UPDATE yourTableName SET yourColumnName=NULL;
Let us first create a table −
mysql> create table insertNullValue
-> (
-> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> ClientName varchar(100),
-> ClientCountryName varchar(20)
-> );
Query OK, 0 rows affected (0.54 sec)
Following is the query to insert some records in the table using insert command −
mysql> insert into insertNullValue(ClientName,ClientCountryName) values('Larry','US');
Query OK, 1 row affected (0.19 sec)
mysql> insert into insertNullValue(ClientName,ClientCountryName) values('David','AUS');
Query OK, 1 row affected (0.09 sec)
mysql> insert into insertNullValue(ClientName,ClientCountryName) values('Bob','UK');
Query OK, 1 row affected (0.17 sec)Following is the query to display all records from the table using select statement −
mysql> select * from insertNullValue;
This will produce the following output −
+----+------------+-------------------+
| Id | ClientName | ClientCountryName |
+----+------------+-------------------+
| 1 | Larry | US |
| 2 | David | AUS |
| 3 | Bob | UK |
+----+------------+-------------------+
3 rows in set (0.00 sec)
Following is the query to insert NULL value for a column −
mysql> update insertNullValue set ClientCountryName=NULL;
Query OK, 3 rows affected (0.19 sec)
Rows matched: 3 Changed: 3 Warnings: 0
Let us check the NULL value is inserted for the column ‘ClientCountryName’ or not. Following is the query −
mysql> select * from insertNullValue;
This will produce the following output displaying the NULL values −
+----+------------+-------------------+
| Id | ClientName | ClientCountryName |
+----+------------+-------------------+
| 1 | Larry | NULL |
| 2 | David | NULL |
| 3 | Bob | NULL |
+----+------------+-------------------+
3 rows in set (0.00 sec)
Published on 16-Apr-2019 16:34:47
