It might be frustrating when trying to query for a record that, without knowing, has a leading or trailing space on a string column.
Lets say that you have a User record with ‘ email@example.com ‘ as email attribute, one easy way to find this record is using the TRIM string function in MySQL:
SELECT * FROM users WHERE TRIM(email)='email@example.com';
Now, to permanently remove such spaces, you can do an UPDATE on the Users table:
UPDATE users SET email=TRIM(email) WHERE email LIKE ' %;
Notice how I’m using the LIKE operand, this makes it easier to find such records.