Rails 5搜索具有多对多关系的ActiveRecords以匹配字段(Rails 5 search ActiveRecords with many to many relationship for

Rails 5搜索具有多对多关系的ActiveRecords以匹配字段(Rails 5 search ActiveRecords with many to many relationship for matching fields)

我有两个模型，通过另一个模型定义了多对多关系。 在这种情况下，用户属于许多组。 每个组可以有很多用户。 通过会员模型定义关系，会员模型也具有其成员资格的状态，即

user.rb

class User < ApplicationRecord has_many :memberships has_many :groups, through: :memberships end

group.rb

class Group < ApplicationRecord has_many :memberships has_many :users, through: :memberships end

membership.rb

class Membership < ApplicationRecord belongs_to :user belongs_to :group enum status: [ :non_member, :pending, :member ] end

当我创建一个新组时，它总是为创建它的用户创建一个成员资格。 其他用户以后会为组创建成员身份。

在我的一个视图中，我想显示当前用户所属的所有组。 所以我可以这样做：

<% @user.groups.each do |group| %> <p><%= group.name %> <% end %>

然后，我想要显示用户不属于的所有组，以便他们可以请求加入。 我尝试了这个，但它返回所有记录，即使我的用户是一个组的成员。

<% Group.joins(:users).where.not(:users => { :id => current_user.id }).each do |group| %>

有没有更好的方法来实现这一目标？

I have two models with a many-to-many relationship defined through another model. In this case A user belongs to many groups. And each group can have many users. There relationship is defined through a Membership model, which also has the status of their membership i.e.

user.rb

class User < ApplicationRecord has_many :memberships has_many :groups, through: :memberships end

group.rb

class Group < ApplicationRecord has_many :memberships has_many :users, through: :memberships end

membership.rb

class Membership < ApplicationRecord belongs_to :user belongs_to :group enum status: [ :non_member, :pending, :member ] end

When I create a new group, It always creates a membership for the user who created it. At a later date other users create memberships for a group.

Within one of my views, I want to show all groups that the current user belongs to. So I can do something like this:

<% @user.groups.each do |group| %> <p><%= group.name %> <% end %>

I then want to show all the groups that a user does not belong to, so that they can request to join. I tried this, but it returns all records, even though my user is a member of one group.

<% Group.joins(:users).where.not(:users => { :id => current_user.id }).each do |group| %>

Is there a better way to achieve this?

最满意答案

class User < ApplicationRecord has_many :memberships has_many :groups, through: :memberships def unjoined_groups Group.where.not(id: group_ids) end def unjoined_groups_by_membership_status(status) Group.includes(:memberships) .where.not(id: group_ids) .where(memberships: { status: status }) end end

试试这个......

class User < ApplicationRecord has_many :memberships has_many :groups, through: :memberships def unjoined_groups Group.where.not(id: group_ids) end def unjoined_groups_by_membership_status(status) Group.includes(:memberships) .where.not(id: group_ids) .where(memberships: { status: status }) end end

Try this instead...