All CHAR and VARCHAR values in MySQL are compared without regard to any trailing spaces : Char Varchar « Data Types « MySQL Tutorial

1. MySQL Tutorial
2. Data Types
3. Char Varchar

mysql>
mysql> CREATE TABLE myTable (myname CHAR(10), yourname VARCHAR(10));
Query OK, 0 rows affected (0.03 sec)

mysql>
mysql> INSERT INTO myTable VALUES ('Monty ', 'Monty ');
Query OK, 1 row affected (0.01 sec)

mysql>
mysql> SELECT myname = 'Monty  ', yourname = 'Monty  ' FROM myTable;
+--------------------+----------------------+
| myname = 'Monty  ' | yourname = 'Monty  ' |
+--------------------+----------------------+
|                  1 |                    1 |
+--------------------+----------------------+
1 row in set (0.00 sec)

mysql>
mysql> drop table myTable;
Query OK, 0 rows affected (0.02 sec)

mysql>
mysql>