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outer joins models that are not associations


use find_by_sql to implement such scenarios.

otherwise as a rule of thumb, if you can't use joins like this Blog.joins(articles: :comments) you are probably doing something bad or use find_by_sql instead.

in a complex case, i'm writing my query in SQL first to verify the logic involved. often times it's trivial to replace one complex query with 2 simple ones (using IN(*ids)).


Categories : SQL

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