我有一个函数，Appointment#serializable_hash看起来像这样：
def serializable_hash(options={})
options = {
:methods => %w(
notes
client
services
products
has_payments
start_time_ymd
start_time_time
calculated_length
day_of_week_index
services_with_info
products_with_info
payments_with_info
stylist_name_index
time_block_type_code
client_name_that_fits
minutes_since_midnight
generous_calculated_length
)}.update(options)
super(options)
end
当我在现有Appointment对象上调用该函数时，SQL 运行如下所示：
Appointment Load (4.6ms) SELECT "appointment".* FROM "appointment" ORDER BY start_time DESC LIMIT 1
Appointment Load (0.6ms) SELECT "appointment".* FROM "appointment" WHERE "appointment"."id" = $1 LIMIT 1 [["id", 4533]]
Client Load (0.7ms) SELECT "client".* FROM "client" WHERE "client"."id" = 398 LIMIT 1
Address Load (0.5ms) SELECT "address".* FROM "address" WHERE "address"."id" = 10 LIMIT 1
(15.4ms) SELECT COUNT(*) FROM "payment" WHERE "payment"."appointment_id" = 4533
TimeBlockType Load (11.1ms) SELECT "time_block_type".* FROM "time_block_type" WHERE "time_block_type"."id" = 2 LIMIT 1
AppointmentService Load (30.3ms) SELECT "appointment_service".* FROM "appointment_service" WHERE "appointment_service"."appointment_id" = 4533
Service Load (18.7ms) SELECT "service".* FROM "service" WHERE "service"."id" = 295 ORDER BY name LIMIT 1
AppointmentProduct Load (6.2ms) SELECT "appointment_product".* FROM "appointment_product" WHERE "appointment_product"."appointment_id" = 4533
Payment Load (0.5ms) SELECT "payment".* FROM "payment" WHERE "payment"."appointment_id" = 4533
Stylist Load (15.5ms) SELECT "stylist".* FROM "stylist" WHERE "stylist"."active" = 't' AND "stylist"."id" = 84 LIMIT 1
StylistEmploymentType Load (0.7ms) SELECT "stylist_employment_type".* FROM "stylist_employment_type" WHERE "stylist_employment_type"."code" = 'CHAIR_RENTAL' LIMIT 1
Salon Load (0.7ms) SELECT "salon".* FROM "salon" WHERE "salon"."id" = 29 LIMIT 1
Stylist Load (1.0ms) SELECT "stylist".* FROM "stylist" WHERE "stylist"."active" = 't' AND (salon_id = 29 AND active = true AND name != 'R.')
StylistEmploymentType Load (0.3ms) SELECT "stylist_employment_type".* FROM "stylist_employment_type" WHERE "stylist_employment_type"."code" = 'CHAIR_RENTAL' LIMIT 1
StylistEmploymentType Load (0.3ms) SELECT "stylist_employment_type".* FROM "stylist_employment_type" WHERE "stylist_employment_type"."code" = 'CHAIR_RENTAL' LIMIT 1
StylistEmploymentType Load (0.3ms) SELECT "stylist_employment_type".* FROM "stylist_employment_type" WHERE "stylist_employment_type"."code" = 'CHAIR_RENTAL' LIMIT 1
StylistEmploymentType Load (0.3ms) SELECT "stylist_employment_type".* FROM "stylist_employment_type" WHERE "stylist_employment_type"."code" = 'CHAIR_RENTAL' LIMIT 1
StylistEmploymentType Load (0.3ms) SELECT "stylist_employment_type".* FROM "stylist_employment_type" WHERE "stylist_employment_type"."code" = 'CHAIR_RENTAL' LIMIT 1
StylistEmploymentType Load (0.2ms) SELECT "stylist_employment_type".* FROM "stylist_employment_type" WHERE "stylist_employment_type"."code" = 'CHAIR_RENTAL' LIMIT 1
Service Load (3.6ms) SELECT "service".* FROM "service" INNER JOIN "appointment_service" ON "service"."id" = "appointment_service"."service_id" WHERE "appointment_service"."appointment_id" = 4533 ORDER BY name
Product Load (16.5ms) SELECT "product".* FROM "product" INNER JOIN "appointment_product" ON "product"."id" = "appointment_product"."product_id" WHERE "appointment_product"."appointment_id" = 4533 ORDER BY brand_id, name
显然，这比它可能的效率要低。如何serializable_hash在尽可能少的查询中运行？有没有更好的方法来做我正在做的事情，而不是参与serializable_hash？