Alternative to ActiveRelationResource which does not produce extra DB queries

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Description

One thing that changed significantly in 0.10 is the introduction of ActiveRelationResource, which seems to be a nice optimization to have when caching is utilized. But when caching is not turned on it actually doubles the amount of DB queries needed to process a request. For example, typical request with include would look something like this in the log on 0.10.x:

DEBUG -- :    (0.0ms)  SELECT "users"."id" AS "users_id", "users"."id" FROM "users" ORDER BY users.id asc LIMIT ? OFFSET ?  [["LIMIT", 10], ["OFFSET", 0]]
DEBUG -- :    (0.1ms)  SELECT DISTINCT users.id AS "source_id", "profiles"."id" AS "profiles_id", "profiles"."id" FROM "users" INNER JOIN "profiles" ON "profiles"."user_id" = "users"."id" WHERE "users"."id" IN (?, ?, ?) ORDER BY profiles.id asc  [["id", 1], ["id", 2], ["id", 3]]
DEBUG -- :    (0.0ms)  SELECT DISTINCT users.id AS "source_id", "posts"."id" AS "posts_id", "posts"."id" FROM "users" INNER JOIN "posts" ON "posts"."user_id" = "users"."id" WHERE "users"."id" IN (?, ?, ?) ORDER BY posts.id asc  [["id", 1], ["id", 2], ["id", 3]]
DEBUG -- :   User Load (0.0ms)  SELECT "users".* FROM "users" WHERE "users"."id" IN (?, ?, ?)  [["id", 1], ["id", 2], ["id", 3]]
DEBUG -- :   Profile Load (0.0ms)  SELECT "profiles".* FROM "profiles" WHERE "profiles"."id" IN (?, ?, ?)  [["id", 1], ["id", 2], ["id", 3]]
DEBUG -- :   Post Load (0.0ms)  SELECT "posts".* FROM "posts" WHERE "posts"."id" IN (?, ?, ?, ?, ?, ?, ?, ?, ?)  [["id", 1], ["id", 2], ["id", 3], ["id", 4], ["id", 5], ["id", 6], ["id", 7], ["id", 8], ["id", 9]]
DEBUG -- :    (0.0ms)  SELECT COUNT(*) FROM "users"

Compare to the same request on 0.9:

DEBUG -- :   User Load (0.0ms)  SELECT "users".* FROM "users" ORDER BY "users"."id" ASC LIMIT ? OFFSET ?  [["LIMIT", 10], ["OFFSET", 0]]
DEBUG -- :   Profile Load (0.1ms)  SELECT "profiles".* FROM "profiles" WHERE "profiles"."user_id" IN (?, ?, ?)  [["user_id", 1], ["user_id", 2], ["user_id", 3]]
DEBUG -- :   Post Load (0.0ms)  SELECT "posts".* FROM "posts" WHERE "posts"."user_id" IN (?, ?, ?)  [["user_id", 1], ["user_id", 2], ["user_id", 3]]
DEBUG -- :    (0.0ms)  SELECT COUNT(*) FROM "users"

Is there a plan to optimize non-cached scenario? Like having an alternative base resource that I'd behave more or less like 0.9 behaved? Thanks.

Inizia tracciando il percorso non memorizzato nella cache di ActiveRelationResource per le richieste con include e confrontalo con i log delle query di 0.9 e 0.10 mostrati qui. Il lavoro è completato quando un’alternativa o un’ottimizzazione evita le query aggiuntive sulle relazioni e sugli id senza caching, preservando i record inclusi e il comportamento della paginazione.