Ruby-on-rails ActiveRecord where field = ? 可能值的数组
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ActiveRecord where field = ? array of possible values
提问by quantumpotato
I want to do
我想要做
Model.where('id = ?', [array of values])
How do I accomplish this look up without chaining OR statements together?
如何在不将 OR 语句链接在一起的情况下完成此查找？
回答by Will Richardson
回答by messanjah
From the ActiveRecord Query Interface guide
If you want to find records using the IN expression you can pass an array to the conditions hash:
如果要使用 IN 表达式查找记录，可以将数组传递给条件哈希：
Client.where(orders_count: [1,3,5])
回答by Selfish
For readability, this can be simplified even further, to:
为了可读性，这可以进一步简化为：
Model.find_by(id: [array of values])
This is equivalent to using where, but more explicit:
这相当于 using where，但更明确：
Model.where(id: [array of values])
回答by BinaryMan
You can use the 'in' operator:
您可以使用“in”运算符：
Model.in(id: [array of values])
回答by Prithviraj Pillai
If you are looking for a query in mongoid this is the oneModel.where(:field.in => ["value1", "value2"] ).all.to_a
如果您正在寻找 mongoid 中的查询，这就是Model.where(:field.in => ["value1", "value2"] ).all.to_a
回答by mmsilviu
There is a 'small' difference between whereand find_by.
where和find_by之间存在“小”差异。
find_bywill return just one record if found otherwise it will be nil.
如果找到，find_by将只返回一条记录，否则它将为零。
Finds the first record matching the specified conditions. There is no implied ordering so if order matters, you should specify it yourself. If no record is found, returns nil.
查找与指定条件匹配的第一条记录。没有隐含的顺序，所以如果顺序很重要，你应该自己指定。如果没有找到记录，则返回 nil。
def find_by(*args)
where(*args).take
rescue RangeError
nil
end
meanwhile whereit will return an relation
同时在那里它将返回一个关系
Returns a new relation, which is the result of filtering the current relation according to the conditions in the arguments.
返回一个新的关系，它是根据参数中的条件过滤当前关系的结果。
So, in your situation the appropriate code is:
因此，在您的情况下，适当的代码是：
Model.where(id: [array of values])
