如何在Ruby on Rails中实现此SQL查询
[英]How do I implement this SQL query in Ruby on Rails
问题描述
我在这里有这个美味的SQL查询，我试图找出如何使用其活动记录方法在Rails中实现==> .select（）.where（）等...
SELECT topics.id FROM topics WHERE NOT EXISTS ( SELECT * FROM votes WHERE votes.topic_id = topics.id )
1 个解决方案
解决方案1
1 已采纳 2017-03-30 07:00:44
尝试这个
@topics = Topic.where("not exists (SELECT * FROM votes WHERE votes.topic_id = topics.id)")
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