我应该如何在使用 'first_or_create' 时合并散列
How should I merge hash while using 'first_or_create'
我有这个哈希，它是动态构建的：
additional_values = {"grouping_id"=>1}
我想在通过 first_or_create 创建后将其与此记录对象合并：
result = model.where(name: 'test').first_or_create do |record|
# I'm trying to merge any record attributes that exist in my hash:
record.attributes.merge(additional_values)
# This works, but it sucks:
# record.grouping_id = data['grouping_id'] if model.name == 'Grouping'
end
#Not working:
#result.attributes>>{"id"=>1, "name"=>"Test", "grouping_id"=>nil}
我知道如果记录已经存在（通过 'first' 返回），它将不会被更新...虽然那将是一个不错的选择并且欢迎任何相关建议，但是 table 刚刚删除并重新创建，所以这不是问题。
我错过了什么？
我也尝试使用 to_sym，结果是：
additional_values = {:grouping_id=>1}
...以防出现一些我不知道的怪事...没有什么不同
问题是Hash#merge returns a new hash and then you aren't doing anything with that hash, you're just throwing it away. I would also suggest sticking to using the ActiveRecord methods for updating attributes, instead of trying to manipulate the underlying hash, such as using assign_attributes or, if you want to save the record update. Though, you may find the create_with, which can be used with find_or_create_by，在这里有用：
model.create_with(additional_values).find_or_create_by(name: 'test')
我在最近的 rails 版本中找不到任何我喜欢的 first_or_create 的文档（如果有的话），但是如果你喜欢它而不是 find_or_create_by，那么如果我们看看 Rails 3 documentation for first_or_create，你应该可以不用 create_with:
model.where(name: 'test').first_or_create(additional_attributes)
我有这个哈希，它是动态构建的：
additional_values = {"grouping_id"=>1}
我想在通过 first_or_create 创建后将其与此记录对象合并：
result = model.where(name: 'test').first_or_create do |record|
# I'm trying to merge any record attributes that exist in my hash:
record.attributes.merge(additional_values)
# This works, but it sucks:
# record.grouping_id = data['grouping_id'] if model.name == 'Grouping'
end
#Not working:
#result.attributes>>{"id"=>1, "name"=>"Test", "grouping_id"=>nil}
我知道如果记录已经存在（通过 'first' 返回），它将不会被更新...虽然那将是一个不错的选择并且欢迎任何相关建议，但是 table 刚刚删除并重新创建，所以这不是问题。
我错过了什么？
我也尝试使用 to_sym，结果是：
additional_values = {:grouping_id=>1}
...以防出现一些我不知道的怪事...没有什么不同
问题是Hash#merge returns a new hash and then you aren't doing anything with that hash, you're just throwing it away. I would also suggest sticking to using the ActiveRecord methods for updating attributes, instead of trying to manipulate the underlying hash, such as using assign_attributes or, if you want to save the record update. Though, you may find the create_with, which can be used with find_or_create_by，在这里有用：
model.create_with(additional_values).find_or_create_by(name: 'test')
我在最近的 rails 版本中找不到任何我喜欢的 first_or_create 的文档（如果有的话），但是如果你喜欢它而不是 find_or_create_by，那么如果我们看看 Rails 3 documentation for first_or_create，你应该可以不用 create_with:
model.where(name: 'test').first_or_create(additional_attributes)