instance method `joins`

Ruby on Rails 6.1.7.10

Since v3.0.20

Available in: v3.0.20 v3.1.12 v3.2.22.5 v4.0.13 v4.1.16 v4.2.9 v5.2.8.1 v6.0.6 v6.1.7.10 v7.0.10 v7.1.6 v7.2.3 v8.0.4 v8.1.2

Compare with:

joins(*args)

Performs a joins on args. The given symbol(s) should match the name of the association(s).

User.joins(:posts)
# SELECT "users".*
# FROM "users"
# INNER JOIN "posts" ON "posts"."user_id" = "users"."id"

Multiple joins:

User.joins(:posts, :account)
# SELECT "users".*
# FROM "users"
# INNER JOIN "posts" ON "posts"."user_id" = "users"."id"
# INNER JOIN "accounts" ON "accounts"."id" = "users"."account_id"

Nested joins:

User.joins(posts: [:comments])
# SELECT "users".*
# FROM "users"
# INNER JOIN "posts" ON "posts"."user_id" = "users"."id"
# INNER JOIN "comments" ON "comments"."post_id" = "posts"."id"

You can use strings in order to customize your joins:

User.joins("LEFT JOIN bookmarks ON bookmarks.bookmarkable_type = 'Post' AND bookmarks.user_id = users.id")
# SELECT "users".* FROM "users" LEFT JOIN bookmarks ON bookmarks.bookmarkable_type = 'Post' AND bookmarks.user_id = users.id

Parameters

args rest

Source

# File activerecord/lib/active_record/relation/query_methods.rb, line 489
    def joins(*args)
      check_if_method_has_arguments!(:joins, args)
      spawn.joins!(*args)
    end

Defined in activerecord/lib/active_record/relation/query_methods.rb line 489 · View on GitHub · Improve this page · Find usages on GitHub

Defined in ActiveRecord::QueryMethods

Signature

Parameters