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How do I delete blank rows in MySQL?
Use the delete command to delete blank rows in MySQL.
The syntax is as follows
delete from yourTableName where yourColumnName=' ' OR yourColumnName IS NULL;
The above syntax will delete blank rows as well as NULL row.
To understand the concept, let us create a table.The query to create a table is as follows
mysql> create table deleteRowDemo -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> StudentName varchar(20) -> ); Query OK, 0 rows affected (0.57 sec)
Insert some records in the table using insert command.
The query is as follows
mysql> insert into deleteRowDemo(StudentName) values('John');
Query OK, 1 row affected (0.13 sec)
mysql> insert into deleteRowDemo(StudentName) values('');
Query OK, 1 row affected (0.18 sec)
mysql> insert into deleteRowDemo(StudentName) values('');
Query OK, 1 row affected (0.14 sec)
mysql> insert into deleteRowDemo(StudentName) values(NULL);
Query OK, 1 row affected (0.13 sec)
mysql> insert into deleteRowDemo(StudentName) values('Carol');
Query OK, 1 row affected (0.13 sec)
mysql> insert into deleteRowDemo(StudentName) values('Bob');
Query OK, 1 row affected (0.14 sec)
mysql> insert into deleteRowDemo(StudentName) values('');
Query OK, 1 row affected (0.18 sec)
mysql> insert into deleteRowDemo(StudentName) values('David');
Query OK, 1 row affected (0.35 sec)Display all records from the table using select statement.
The query is as follows
mysql> select *from deleteRowDemo;
The following is the output
+----+-------------+ | Id | StudentName | +----+-------------+ | 1 | John | | 2 | | | 3 | | | 4 | NULL | | 5 | Carol | | 6 | Bob | | 7 | | | 8 | David | +----+-------------+ 8 rows in set (0.00 sec)
Here is the query to delete blank rows as well as NULL
mysql> delete from deleteRowDemo where StudentName='' OR StudentName IS NULL; Query OK, 4 rows affected (0.18 sec)
Now let us check the table records once again.
The query is as follows
mysql> select *from deleteRowDemo;
The following is the output
+----+-------------+ | Id | StudentName | +----+-------------+ | 1 | John | | 5 | Carol | | 6 | Bob | | 8 | David | +----+-------------+ 4 rows in set (0.00 sec)
Updated on: 30-Jul-2019
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