Today I Learned

A Hashrocket project

One query with Select In

Today I learned that if you pass an ActiveRecord::Relation as param to where Rails will create a single query using IN and an inner SELECT:

Repository.where(user_id: User.active.select(:id))
=>  Repository Load (1.1ms)
        SELECT "repositories".*
        FROM "repositories"
        WHERE "repositories"."user_id" IN (
          SELECT "users"."id"
          FROM "users"
          WHERE "users"."status" == 1
       )

h/t @mattpolito

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