To remove NULL records in a column, you can use delete command. Following is the syntax −
delete from yourTableName where yourColumnName IS NULL;
Let us first create a table −
mysql> create table removeNullRecordsDemo -> ( -> Name varchar(100) -> ); Query OK, 0 rows affected (0.50 sec)
Following is the query to insert records in the table using insert command −
mysql> insert into removeNullRecordsDemo values('John'); Query OK, 1 row affected (0.14 sec) mysql> insert into removeNullRecordsDemo values(null); Query OK, 1 row affected (0.15 sec) mysql> insert into removeNullRecordsDemo values('Larry'); Query OK, 1 row affected (0.19 sec) mysql> insert into removeNullRecordsDemo values('Bob'); Query OK, 1 row affected (0.12 sec) mysql> insert into removeNullRecordsDemo values(null); Query OK, 1 row affected (0.13 sec) mysql> insert into removeNullRecordsDemo values('David'); Query OK, 1 row affected (0.18 sec) mysql> insert into removeNullRecordsDemo values(null); Query OK, 1 row affected (0.22 sec)
Following is the query to display all records from the table using select statement −
mysql> select *from removeNullRecordsDemo;
This will produce the following output −
+-------+ | Name | +-------+ | John | | NULL | | Larry | | Bob | | NULL | | David | | NULL | +-------+ 7 rows in set (0.00 sec)
Let us now remove NULL records in the above column −
mysql> delete from removeNullRecordsDemo where Name IS NULL; Query OK, 3 rows affected (0.16 sec)
Check the null records have been removed from column or not −
mysql> select * from removeNullRecordsDemo;
Following is the output displaying all records except NULL −
+-------+ | Name | +-------+ | John | | Larry | | Bob | | David | +-------+ 4 rows in set (0.00 sec)