mysql - RoR scaffold add field after script/generate -

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i generated scaffold , put in type:value need add field / db column how add type:value without destroying , restarting whole project?

rake aborted! mysql::error: have error in sql syntax; check manual corres ponds mysql server version right syntax use near '(11), `titl e` varchar(255) default null, `artist_old` varchar(255) default null,' @ line 1 : create table `albums` (`id` int(11) default null auto_increment primary key(11 ), `title` varchar(255) default null, `artist_old` varchar(255) default null, `r elease_date` datetime default null, `genre` varchar(255) default null, `feature`  int(11) default null, `image_path` varchar(255) default null, `created_at` date time default null, `updated_at` datetime default null, `artist_id` int(11) defau lt null) engine=innodb

usually when use scaffold command create migration in db/migrate/ folder, containing database setup model, example:

class createcomments < activerecord::migration   def self.up     create_table :comments |t|       t.text :body     end   end    def self.down     drop_table :comments   end end

if have not run rake db:migrate command after created scaffold, can edit migration file under db/migrate/ , add field missed in beginning. after edited file, run rake db:migrate command apply migration database.

if stepped through rake db:migrate after creating scaffold, can create new migration script/generate migration addsubjectcolumntocomments add field table. in example above, new migration , fill in following code:

class addsubjectcolumntocomments < activerecord::migration   def self.up     add_column :subject, :comments, :string   end    def self.down     remove_column :subject, :comments   end

good luck migrating!


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