在Rails中加载渴望加载的关联的最快方法
[英]Fastest way to load eager loaded associations in Rails
问题描述
I have a Contract which belongs to a Provider , and I am doing this: 
我有一个属于Provider的Contract ，我正在这样做：
@contracts = Contract.where(provider_id: provider_ids).includes(:provider)
And I want to get the distinct providers: 我想获得不同的提供者：
@providers = @contracts.map(&:provider).uniq
Is there a way to make DB do all the work? 有没有一种方法可以使DB完成所有工作？ ie map is making Ruby work. 即地图使Ruby正常工作。
1 个解决方案
解决方案1
0 2014-08-01 20:32:42
为什么不这样做
Provider.find Contract.select("distinct provider_id")
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