require "active_record"
require "activerecord-import" # https://github.com/zdennis/activerecord-import

ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
ActiveRecord::Migration.class_eval do
  create_table(:records) do |t|
    t.string :column
  end
end

data = 50_000.times.map { |i| Hash[column: "Column #{i}"] }

# =============================================================

class Record < ActiveRecord::Base
end

Record.import(data.first.keys, data.map(&:values), validate: false)

# Takes 2 seconds (like the SQL version), but it's an additional dependency.