ruby on rails migrations using an existing table

Question

I have this problem. I need to use an existing table on a mysql database. The name of the table is not compatible with RoR conventions and I need to remap the table name and the name of the attributes. I have created a scaffold to visualize on a web page the content of the table but I can't change the mapping. Is there a solution to indicate to RoR the relation between the name of the class and the name of the table in the database? and a solution to indicate the relation between the attribute of the class and field on the table? Thanks.

Igor Drozdov · Accepted Answer · 2018-05-30 06:15:09Z

1

The table name can be specified using table_name class method.

For the attributes/column, you need to explicitly specify aliases for the attributes using alias_attribute method. For example, if you have name_of_thing column, but want to treat it as name, then you need something like this in your model:

class CreateUtenti < ActiveRecord::Base
  self.table_name = "another_name"
  alias_attribute :name, :name_of_thing
end

edited May 30, 2018 at 6:15

answered May 29, 2018 at 11:27

Igor Drozdov

15.1k5 gold badges39 silver badges55 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Giovanni Di Clemente Over a year ago

Thanks to you too. In this case rake db:migrate give me this error: rake aborted! NoMethodError: undefined method `table_name=' for CreateUtenti:Class

Igor Drozdov Over a year ago

@GiovanniDiClemente does your CreateUtenti class inherits from ActiveRecord::Base?

Igor Drozdov Over a year ago

what Rails version do you use?

Kaushlendra Tomar · Accepted Answer · 2018-05-29 11:24:46Z

0

Yes you can pass table name in model like:

class YourModel < ActiveRecord::Base
  self.table_name = "pass_table_name_here"
end

answered May 29, 2018 at 11:24

Kaushlendra Tomar

1,45010 silver badges16 bronze badges

2 Comments

Giovanni Di Clemente Over a year ago

Thank for your answer. I have tried but rake db:migrate give me an error: rake aborted! ArgumentError: wrong number of arguments (given 2, expected 0..1)

Giovanni Di Clemente Over a year ago

Caused by: ArgumentError: wrong number of arguments (given 2, expected 0..1) Tasks: TOP => db:migrate (See full trace by running task with --trace) Macintosh:telwebtt giovannidiclemente$ rake db:migrate --trace ** Invoke db:migrate (first_time) ** Invoke db:load_config (first_time) ** Invoke environment (first_time) ** Execute environment ** Execute db:load_config ** Execute db:migrate rake aborted! ArgumentError: wrong number of arguments (given 2, expected 0..1)

Collectives™ on Stack Overflow

ruby on rails migrations using an existing table

2 Answers 2

3 Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related