rails-question-getting-x-where-there-are-no-y.org

[Rails Question] Getting X where there are no Y

WARNING: This is old and likely obsolete.

• published date: 2015-03-03 05:38
• keywords: [“code”, “examples”, “questions”, “rails”, “ruby”]
• source: https://github.com/tamouse/example_questions_without_answers

There was a question recently in the #RubyOnRails IRC channel on freenode: “How can I retrieve all the questions that don’t have answers?”. This Rails coding example shows the answer.

Two Models

• Question
• Answer

Associations

• Question has_many Answers
• Answer belongs_to Question

Finding Questions with No Answers:

Question.includes(:answers).where(answers: {id: nil})

Converse: Finding All Questions that have Answers:

Question.includes(:answers).where.not(answers: {id: nil})