Rails4のトップモデルと関連モデルの両方で.includes（）プラス.where（）を書くにはどうしたらいいですか？

Question

私はこのクエリで間違って何が起こっていたか任意のアイデアを持っていなかった。

@customers = 
     Customer.includes(:phone_numbers, :emails) 
     .select("first_name, last_name, zip_code, customers.id, street1, street2") 
     .where(:merchant_id => environment) 
     .where("phone_numbers.number ~* :key", 
       :key => key, :digits => digits) 

それはRails3で罰金働いていました。

私はRails4で解決するのに役立つドキュメントhereに遭遇しましたが、このクエリを書くより良い方法があるかどうかを知りたいと思います。

それは（これは危ないです...）以下の生成：あなたは私はあなたがjoinないincludesを使用したいと思いますphone_numbersまたはemails内のフィールドのいずれかを選択していないので

"SELECT first_name, last_name, zip_code, customers.id, street1, street2, "customers"."id" AS t0_r0, "customers"."account_id" AS t0_r1, "customers"."first_name" AS t0_r2, "customers"."last_name" AS t0_r3, "customers"."street1" AS t0_r4, "customers"."street2" AS t0_r5, "customers"."city_id" AS t0_r6, "customers"."city" AS t0_r7, "customers"."state" AS t0_r8, "customers"."state_id" AS t0_r9, "customers"."zip_code" AS t0_r10, "customers"."country" AS t0_r11, "customers"."municipality" AS t0_r12, "customers"."latitude" AS t0_r13, "customers"."longitude" AS t0_r14, "customers"."location" AS t0_r15, "customers"."customer_type" AS t0_r16, "customers"."notes" AS t0_r17, "customers"."birthday" AS t0_r18, "customers"."merchant_id" AS t0_r19, "customers"."gmaps" AS t0_r20, "customers"."marketing" AS t0_r21, "customers"."communication_method" AS t0_r22, "customers"."account_status" AS t0_r23, "customers"."account_type" AS t0_r24, "customers"."created_at" AS t0_r25, "customers"."updated_at" AS t0_r26, "customers"."api_customer_id" AS t0_r27, "customers"."api_updated_at" AS t0_r28, "phone_numbers"."id" AS t1_r0, "phone_numbers"."customer_id" AS t1_r1, "phone_numbers"."account_id" AS t1_r2, "phone_numbers"."contact_id" AS t1_r3, "phone_numbers"."number" AS t1_r4, "phone_numbers"."country_code" AS t1_r5, "phone_numbers"."area_code" AS t1_r6, "phone_numbers"."extension" AS t1_r7, "phone_numbers"."created_at" AS t1_r8, "phone_numbers"."updated_at" AS t1_r9, "emails"."id" AS t2_r0, "emails"."customer_id" AS t2_r1, "emails"."account_id" AS t2_r2, "emails"."contact_id" AS t2_r3, "emails"."address" AS t2_r4, "emails"."created_at" AS t2_r5, "emails"."updated_at" AS t2_r6 
FROM "customers" 
LEFT OUTER JOIN "phone_numbers" ON "phone_numbers"."customer_id" = "customers"."id" 
LEFT OUTER JOIN "emails" ON "emails"."customer_id" = "customers"."id" 
WHERE "customers"."merchant_id" = 29 AND (phone_numbers.number ~* '424298')" 

Answer 1

を。トリッキーなビットは、LEFT OUTERを動作させることです。

http://apidock.com/rails/v4.2.1/ActiveRecord/QueryMethods/joins

多分このような何か。

Customer. 
    select("first_name, last_name, zip_code, customers.id, street1, street2"). 
    joins("LEFT OUTER JOIN phone_numbers ON phone_numbers.customer_id = customers.id"). 
    joins("LEFT OUTER JOIN emails ON emails.customer_id = customers.id"). 
    where(:merchant_id => environment). 
    where("phone_numbers.number ~* :key", :key => key, :digits => digits)