add_merchants.rb

require 'awesome_print'
require 'active_record'
require 'pg'
require 'pp'
require 'roo'

ActiveRecord::Base.establish_connection(
  :adapter  => 'postgresql',
  :host     => 'localhost',
  :username => 'kevin',
  :database => 'tinkov_dev',
  :password => '123'
)

class Schema < ActiveRecord::Migration
  def change
    create_table :merchants do |t|
      t.string :name
    end

    add_index :merchants, :name
  end
end

Schema.new.change

# Mdel
class Merchant < ActiveRecord::Base
  attr_accessible :name
end

# Get data from spreadsheet
merchants = Roo::Spreadsheet.open('/Users/kevin/Documents/tin_olimp/merchants.xlsx').to_a

# Add to table
Merchant.transaction do
  merchants.flatten.each { |merchant| Merchant.create!(:name => merchant)}
end