4

我正在尝试使用 5 个表加载结果：

class Meeting < ActiveRecord::Base
  has_many :bookings
end

class Booking < ActiveRecord::Base
  belongs_to :user
  belongs_to :meeting
  belongs_to :role
  belongs_to :group
end

class Group < ActiveRecord::Base
  has_many :group_memberships
  has_many :users, through: :group_memberships
end

class GroupMembership < ActiveRecord::Base
  belongs_to :group
  belongs_to :user
end

class User < ActiveRecord::Base
  has_many :group_memberships
  has_many :groups, through: :group_memberships
end

在 MeetingController.rb 中：

def index
    @meetings = Meeting.where(year: @year)
end

我正在尝试使用 include(:bookings) 但根据bullet-gem急切加载不起作用。在我看来，我称之为这条线：

@meetings.each do |meeting|
  meeting.bookings.find_by(group: @group, role: @role)
end

我得到了多 52 行这段代码，这显然意味着我并不急于加载任何数据：

Booking Load (0.1ms)  SELECT "bookings".* FROM "bookings" WHERE "bookings"."meeting_id" = ? AND "bookings"."user_id" = 8 AND "bookings"."group_id" = 2 LIMIT 1  [["meeting_id", 207]]
  Rendered shared/_book.html.haml (1.0ms)
  Booking Load (0.1ms)  SELECT "bookings".* FROM "bookings" WHERE "bookings"."meeting_id" = ? AND "bookings"."group_id" = 2 AND "bookings"."role_id" = 4 LIMIT 1  [["meeting_id", 208]]
  Booking Load (0.0ms)  SELECT "bookings".* FROM "bookings" WHERE "bookings"."meeting_id" = ? AND "bookings"."user_id" = 8 AND "bookings"."group_id" = 2 LIMIT 1  [["meeting_id", 208]]
  Rendered shared/_book.html.haml (1.0ms)
  Booking Load (0.1ms)  SELECT "bookings".* FROM "bookings" WHERE "bookings"."meeting_id" = ? AND "bookings"."group_id" = 2 AND "bookings"."role_id" = 4 LIMIT 1  [["meeting_id", 209]]

子弹日志：

2014-03-29 15:30:48[WARN] user: karlingen
localhost:3000http://localhost:3000/meetings/host
Unused Eager Loading detected
  Meeting => [:bookings]
  Remove from your finder: :include => [:bookings]

任何想法我应该做什么？

4

2 回答 2

0

尝试以下操作： 

@meetings = Meeting.includes(:bookings).where(year: @year)

另外，你是如何通过@year的？

于 2014-09-27T22:39:15.797 回答
0 
Meeting.includes(:bookings).where(year: @year).references(:bookings)

如果您使用的是rails 4，它将起作用。

于 2015-05-15T09:44:18.157 回答