title: Modifying enum column succeeds, but value is not valid
body: <p>When I execute this statement:</p>
  
  <pre><code>ALTER TABLE person MODIFY COLUMN subcommittee
    ENUM('Arts','Bus','HC','IA','Pol','ST','Floater','Student') NULL DEFAULT NULL;
  </code></pre>
  
  <p>the response is</p>
  
  <pre><code>2801 row(s) affected Records: 2801  Duplicates: 0  Warnings: 0
  </code></pre>
  
  <p>but then this statement:</p>
  
  <pre><code>update person set subcommittee = 'Student' where person_pk = 1381;
  </code></pre>
  
  <p>always results in this error message:</p>
  
  <pre><code>Error Code: 1265. Data truncated for column 'subcommittee' at row 1
  </code></pre>
  
  <p>(Person 1381 is in the database, in case you're wondering, or I wouldn't even have gotten to this error message.)</p>
  
  <p>Choosing another enum works:</p>
  
  <pre><code>update person set subcommittee = 'Floater' where person_pk = 1381;
  
  1 row(s) affected Rows matched: 1  Changed: 1  Warnings: 0
  </code></pre>
  
  <p>I first noticed this when I got the error from my PHP app using PDO, but then reproduced it in MySQLWorkbench, from which the above was taken.</p>
  
  <p>Perhaps deleting the column entirely and redefining it would get around the problem, but this is a live database in which I just want to add one additional enum value (Student).</p>
  
  <p>I have tried retyping the alter statement, copying it to a text editor to examine the characters, and a few other things to rule out weird invisible characters in the value. I also rearranged the values:</p>
  
  <pre><code>ALTER TABLE person MODIFY COLUMN subcommittee
    ENUM('Arts','Bus','HC','IA','Pol','ST', 'Student','Floater') NULL DEFAULT NULL;
  </code></pre>
  
  <p>No joy.</p>
  
  <p>I have seen some bugs related to modifying an enum column when I googled around a bit. Does anyone know if this is a MySQL bug?</p>
  
  <p>(MySQL version 5.5.28.)</p>
  
  <hr>
  
  <p>Some data a few people asked for:</p>
  
  <pre><code>mysql&gt; describe person;
  +------------------------------+-------------------------------------------------------------+------+-----+---------+----------------+
  | Field                        | Type                                                        | Null | Key | Default | Extra          |
  +------------------------------+-------------------------------------------------------------+------+-----+---------+----------------+
  | person_pk                    | int(11)                                                     | NO   | PRI | NULL    | auto_increment |
  | name_last                    | varchar(255)                                                | NO   | MUL |         |                |
  | name_first                   | varchar(255)                                                | YES  |     | NULL    |                |
  | name_index                   | int(11)                                                     | NO   |     | 0       |                |
  | name_middle                  | varchar(255)                                                | YES  |     | NULL    |                |
  | name_spouse_or_partner_first | varchar(255)                                                | YES  |     | NULL    |                |
  | name_spouse_or_partner_last  | varchar(255)                                                | YES  |     | NULL    |                |
  | name_legal_first             | varchar(255)                                                | YES  |     | NULL    |                |
  | name_legal_middle            | varchar(255)                                                | YES  |     | NULL    |                |
  | name_legal_last              | varchar(255)                                                | YES  |     | NULL    |                |
  | prefix                       | varchar(255)                                                | YES  |     | NULL    |                |
  | suffix                       | varchar(255)                                                | YES  |     | NULL    |                |
  | salutation                   | varchar(255)                                                | YES  |     | NULL    |                |
  | home_street1                 | varchar(255)                                                | YES  |     | NULL    |                |
  | home_street2                 | varchar(255)                                                | YES  |     | NULL    |                |
  | home_city                    | varchar(255)                                                | YES  |     | NULL    |                |
  | home_state                   | varchar(255)                                                | YES  |     | NULL    |                |
  | home_zip                     | varchar(255)                                                | YES  |     | NULL    |                |
  | home_country                 | varchar(255)                                                | YES  |     | NULL    |                |
  | work_org                     | varchar(255)                                                | YES  |     | NULL    |                |
  | work_street1                 | varchar(255)                                                | YES  |     | NULL    |                |
  | work_street2                 | varchar(255)                                                | YES  |     | NULL    |                |
  | work_city                    | varchar(255)                                                | YES  |     | NULL    |                |
  | work_state                   | varchar(255)                                                | YES  |     | NULL    |                |
  | work_zip                     | varchar(255)                                                | YES  |     | NULL    |                |
  | work_country                 | varchar(255)                                                | YES  |     | NULL    |                |
  | phone_home                   | varchar(255)                                                | YES  |     | NULL    |                |
  | phone_work                   | varchar(255)                                                | YES  |     | NULL    |                |
  | phone_mobile                 | varchar(255)                                                | YES  |     | NULL    |                |
  | phone_fax                    | varchar(255)                                                | YES  |     | NULL    |                |
  | phone5                       | varchar(255)                                                | YES  |     | NULL    |                |
  | phone6                       | varchar(255)                                                | YES  |     | NULL    |                |
  | email                        | varchar(255)                                                | YES  |     | NULL    |                |
  | email2                       | varchar(255)                                                | YES  |     | NULL    |                |
  | website                      | varchar(255)                                                | YES  |     | NULL    |                |
  | preferred_communication      | enum('home','work','mobile','email','mail','special')       | YES  |     | NULL    |                |
  | preferred_communication_text | varchar(255)                                                | YES  |     | NULL    |                |
  | preferred_address            | enum('home','work')                                         | YES  |     | NULL    |                |
  | use_housing                  | tinyint(1)                                                  | YES  |     | NULL    |                |
  | smoker                       | tinyint(1)                                                  | YES  |     | NULL    |                |
  | pet_allergies                | tinyint(1)                                                  | YES  |     | NULL    |                |
  | pets                         | tinyint(1)                                                  | YES  |     | NULL    |                |
  | kids                         | tinyint(1)                                                  | YES  |     | NULL    |                |
  | physical_considerations      | text                                                        | YES  |     | NULL    |                |
  | dietary_needs                | text                                                        | YES  |     | NULL    |                |
  | appellation                  | varchar(255)                                                | YES  |     | NULL    |                |
  | bio                          | text                                                        | YES  |     | NULL    |                |
  | photo                        | varchar(255)                                                | YES  |     | NULL    |                |
  | include_in_directory         | tinyint(1)                                                  | YES  |     | NULL    |                |
  | participant_notes            | text                                                        | YES  |     | NULL    |                |
  | contact_notes                | text                                                        | YES  |     | NULL    |                |
  | available_1A                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_1P                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_2A                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_2P                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_3A                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_3P                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_4A                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_4P                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_5A                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | available_5P                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | interest_x_dis               | tinyint(1)                                                  | YES  |     | NULL    |                |
  | interest_arts                | tinyint(1)                                                  | YES  |     | NULL    |                |
  | interest_bus                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | interest_hc                  | tinyint(1)                                                  | YES  |     | NULL    |                |
  | interest_ia                  | tinyint(1)                                                  | YES  |     | NULL    |                |
  | interest_med                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | interest_pol                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | interest_st                  | tinyint(1)                                                  | YES  |     | NULL    |                |
  | venue_manager                | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_arts               | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_bus                | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_hc                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_ia                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_pol                | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_st                 | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_students           | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_housing            | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_moderator          | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_volunteer          | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_fundraising        | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_office             | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_other              | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_notes              | text                                                        | YES  |     | NULL    |                |
  | houser_fk                    | int(11)                                                     | YES  | MUL | NULL    |                |
  | housed_fk                    | int(11)                                                     | YES  | MUL | NULL    |                |
  | contact_fk                   | int(11)                                                     | YES  | MUL | NULL    |                |
  | hyphen_fk                    | int(11)                                                     | YES  | MUL | NULL    |                |
  | introduced_by_fk             | int(11)                                                     | YES  | MUL | NULL    |                |
  | committee_contact_fk         | int(11)                                                     | YES  | MUL | NULL    |                |
  | donor                        | tinyint(1)                                                  | YES  |     | NULL    |                |
  | houser                       | tinyint(1)                                                  | YES  |     | NULL    |                |
  | moderator                    | tinyint(1)                                                  | YES  |     | NULL    |                |
  | producer                     | tinyint(1)                                                  | YES  |     | NULL    |                |
  | committee_member             | tinyint(1)                                                  | YES  |     | NULL    |                |
  | participant                  | tinyint(1)                                                  | YES  |     | NULL    |                |
  | fan                          | tinyint(1)                                                  | YES  |     | NULL    |                |
  | student                      | tinyint(1)                                                  | YES  |     | NULL    |                |
  | volunteer                    | tinyint(1)                                                  | YES  |     | NULL    |                |
  | staff                        | tinyint(1)                                                  | YES  |     | NULL    |                |
  | companion                    | tinyint(1)                                                  | YES  |     | NULL    |                |
  | id_number                    | int(11)                                                     | YES  |     | NULL    |                |
  | deceased                     | tinyint(1)                                                  | YES  |     | NULL    |                |
  | load_donation                | tinyint(1)                                                  | YES  |     | NULL    |                |
  | load_panel                   | tinyint(1)                                                  | YES  |     | NULL    |                |
  | load_participant             | tinyint(1)                                                  | YES  |     | NULL    |                |
  | conversion_note              | text                                                        | YES  |     | NULL    |                |
  | replacedby_fk                | int(11)                                                     | YES  | MUL | NULL    |                |
  | companion_to_fk              | int(11)                                                     | YES  | MUL | NULL    |                |
  | name_for_program             | varchar(255)                                                | YES  |     | NULL    |                |
  | gender                       | enum('male','female')                                       | YES  |     | NULL    |                |
  | subcommittee                 | enum('Arts','Bus','HC','IA','Pol','ST','Student','Floater') | YES  |     | NULL    |                |
  | companion_type               | enum('spouse/partner','child','friend')                     | YES  |     | NULL    |                |
  | days_here                    | varchar(6)                                                  | YES  |     | NULL    |                |
  | new_or_returning             | enum('new','returning')                                     | YES  |     | NULL    |                |
  | confirmation_sheet           | tinyint(1)                                                  | YES  |     | NULL    |                |
  | bio_in                       | tinyint(1)                                                  | YES  |     | NULL    |                |
  | photo_in                     | tinyint(1)                                                  | YES  |     | NULL    |                |
  | birthday                     | date                                                        | YES  |     | NULL    |                |
  | date_topics_letter_sent      | date                                                        | YES  |     | NULL    |                |
  | topics_received              | tinyint(1)                                                  | YES  |     | NULL    |                |
  | rating                       | enum('A','B','C','D','F')                                   | YES  |     | NULL    |                |
  | flight_info_received         | tinyint(1)                                                  | YES  |     | NULL    |                |
  | transportation_email_sent    | tinyint(1)                                                  | YES  |     | NULL    |                |
  | bringing_children            | tinyint(1)                                                  | YES  |     | NULL    |                |
  | date_address_verfied         | date                                                        | YES  |     | NULL    |                |
  +------------------------------+-------------------------------------------------------------+------+-----+---------+----------------+
  126 rows in set (0.01 sec)
  
  mysql&gt; select person_pk, subcommittee from person where person_pk = 1381;
  +-----------+--------------+
  | person_pk | subcommittee |
  +-----------+--------------+
  |      1381 | Floater      |
  +-----------+--------------+
  1 row in set (0.00 sec)
  </code></pre>