CODEWITHSUNDEEP
ruby-on-railssqlite
user3735111
user3735111

Reputation: 155

SQLite + rails - working the database

I ended up in a situation where I have a relatively large table, and I need to add a new column to it. Sounds easy enough? Well, there is a catch - I also need to fill that new column with data based on data already present, but I have no idea how to automate this process.

I have columns 'title' and 'title_de', and new column is 'lang'. New column should contain either 'de' or 'eng' depending on if 'title' is blank or not (blank 'title' means it's 'de', non blank means it's 'eng').

How to tackle this?

Upvotes: 0

Views: 23

Answers (1)

aks
aks

Reputation: 9491

You will want to do something like this:

class AddColumnToItems < ActiveRecord::Migration[5.0]
  def change
    add_column :items, :lang, :string
    ActiveRecord::Base.transaction do
      Item.all.each do |item|
        item.lang = "de"
        item.lang = "eng" unless item.title.blank?
        item.save
      end
    end
  end
end

Then:

rake db:migrate

I hope that solves your problem!

Upvotes: 1

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