MySQL query to display only the column values with corresponding column having whitespace

For this, use the TRIM() function. Let us first create a table −

mysql> create table DemoTable826(
   FirstName varchar(100),
   Age int
);
Query OK, 0 rows affected (0.60 sec)

Insert some records in the table using the insert command. Here, we have set the FirstName as whitespace for some of the records −

mysql> insert into DemoTable826 values(' ',24);
Query OK, 1 row affected (0.08 sec)
mysql> insert into DemoTable826 values(' ',22);
Query OK, 1 row affected (0.15 sec)
mysql> insert into DemoTable826 values('Chris',26);
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable826 values('Robert',27);
Query OK, 1 row affected (0.07 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable826 ;

This will produce the following output −

+-----------+------+
| FirstName | Age  |
+-----------+------+
| Adam      | 21   |
|           | 24   |
|           | 22   |
| Chris     | 26   |
| Robert    | 27   |
+-----------+------+
5 rows in set (0.00 sec)

Following is the query to display only the column values with the corresponding column having whitespace −

mysql> select *from DemoTable826 where COALESCE(TRIM(FirstName), '') = '';

This will produce the following output −

+-----------+------+
| FirstName | Age  |
+-----------+------+
|           | 24   |
|           | 22   |
+-----------+------+
2 rows in set (0.00 sec)