“user_item/10001” => “[10001, 101, 1, …]”, “user_item/10002” => “[10002, 101, 2, …]”, “user_item/10003” => “[10003, 101, 3, …]”
} select id from user_items where user_id = 101;
select * from user_items where id in (10001, 10002, 10003); app memcached MySQL UserItem.fetch_by_index(user_id:101) class UserItem < ActiveRecord::Base acts_as_cached(version: 1, expires_in: 1.day) acts_as_cached_by_index(:user_id)
end # indexΛு͍ͬͯΔΧϥϜͷΈࢦఆՄ no cached cached ※Ωϟογϡ͍ͯ͠ͳ͍ࠩͷΈMySQLʹ͍߹ΘͤΔ # جຊతʹexpire͠ͳ͍ # සൟʹexpire͢Δ