Rails 中 create_table 的默认值

Question

我正在填充我使用来自 gem 响应的 rake 创建的表。但是，没有 image_url 的记录返回“nil”。如何设置它以便 rake 自动将“nil”替换为固定值？

namespace :cards do 
    desc "Create cards"
    task :create_cards => :environment do
        cards = MTG::Card.where(page: 50).where(pageSize: 50).all
        cards.each do |card|
            Card.create(name: card.name,multiverse_id: card.multiverse_id, manaCost: card.mana_cost, cmc: card.cmc, cardtype: card.type, rarity: card.rarity, set: card.set, setName: card.set_name, text: card.text, flavor: card.flavor, artist: card.artist, number: card.number, power: card.power, toughness: card.toughness, layout: card.layout, image_url: card.image_url, watermark: card.watermark, original_text: card.original_text, original_type: card.original_type)
        end
    end
end

我想知道这是否是我需要在控制器中做的事情？控制器只是：

class Card < ApplicationRecord
end

我尝试使用 :default => "MyValue" 但它不起作用 - 我假设因为 null /= NIL

欢迎任何意见。

Answer 1

为什么不在循环期间添加检查值是否存在？例如：

namespace :cards do 
    desc "Create cards"
    task :create_cards => :environment do
        cards = MTG::Card.where(page: 50).where(pageSize: 50).all
        card.image_url.blank? ? image_url = 'fixed_val' : image_url = card.image_url
        cards.each do |card|
            Card.create(name: card.name,multiverse_id: card.multiverse_id, manaCost: card.mana_cost, cmc: card.cmc, cardtype: card.type, rarity: card.rarity, set: card.set, setName: card.set_name, text: card.text, flavor: card.flavor, artist: card.artist, number: card.number, power: card.power, toughness: card.toughness, layout: card.layout, image_url: image_url, watermark: card.watermark, original_text: card.original_text, original_type: card.original_type)
        end
    end
end