Rails中调用destroy清除用户Address属性值失败报错求助

我可以通过以下代码设置用户的address属性：

$User.find_by_id(19).update(address: "canada")

但尝试用destroy方法清除该值时失败了：

$User.find_by_id(19).destroy(address: "canada")

执行后得到报错：

$User.find_by_id(19).destroy(address: "canada")
  User Load (1.3ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1  [["id", 19]]
Traceback (most recent call last):
       10: from bin/rails:4:in `<main>'
        9: from bin/rails:4:in `require'
        8: from /app/vendor/bundle/ruby/2.6.0/gems/railties-4.2.11.1/lib/rails/commands.rb:17:in `<top (required)>'
        7: from /app/vendor/bundle/ruby/2.6.0/gems/railties-4.2.11.1/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
        6: from /app/vendor/bundle/ruby/2.6.0/gems/railties-4.2.11.1/lib/rails/commands/commands_tasks.rb:68:in `console'
        5: from /app/vendor/bundle/ruby/2.6.0/gems/railties-4.2.11.1/lib/rails/commands/console.rb:9:in `start'
        4: from /app/vendor/bundle/ruby/2.6.0/gems/railties-4.2.11.1/lib/rails/commands/console.rb:110:in `start'
        3: from (irb):2
        2: from (irb):2:in `rescue in irb_binding'
        1: from /app/vendor/bundle/ruby/2.6.0/gems/activerecord-4.2.11.1/lib/active_record/transactions.rb:280:in `destroy'
ArgumentError (wrong number of arguments (given 1, expected 0))

错误原因 #

destroy方法是用来删除整个数据库记录的，它不需要传入任何参数。你传入address: "canada"属于传参错误，所以触发了ArgumentError。

正确的清除方式 #

要清除单个属性值，应该继续使用update方法，把address设为nil或者空字符串（根据业务需求选择）：

• 设为nil（数据库中存储为NULL）：

$User.find_by_id(19).update(address: nil)

• 设为空字符串：

$User.find_by_id(19).update(address: "")

如果需要更高效的批量操作（注意此方式不会触发模型回调），可以使用update_all：

$User.where(id: 19).update_all(address: nil)

内容的提问来源于stack exchange，提问作者Nour Abu Khajil