diff --git a/app/models/meeting.rb b/app/models/meeting.rb
index 41f0a55ecb..264cddf61f 100644
--- a/app/models/meeting.rb
+++ b/app/models/meeting.rb
@@ -69,7 +69,7 @@ class Meeting < ActiveRecord::Base
   after_initialize :set_initial_values
 
   User.before_destroy do |user|
-    Meeting.update_all ['author_id = ?', DeletedUser.first.id], ['author_id = ?', user.id]
+    Meeting.where(['author_id = ?', user.id]).update_all ['author_id = ?', DeletedUser.first.id]
   end
 
   def start_date
@@ -116,7 +116,7 @@ class Meeting < ActiveRecord::Base
     changeable_participants = participants.select(&:invited).collect(&:user)
     changeable_participants = changeable_participants + participants.select(&:attended).collect(&:user)
     changeable_participants = changeable_participants + \
-                              project.users.all(include: { memberships: [:roles, :project] }).select { |u| self.visible?(u) }
+                              project.users.includes(memberships: [:roles, :project]).select { |u| self.visible?(u) }
 
     changeable_participants.uniq(&:id)
   end
diff --git a/app/models/meeting_content.rb b/app/models/meeting_content.rb
index 60d17ab2cc..8319ecbd26 100644
--- a/app/models/meeting_content.rb
+++ b/app/models/meeting_content.rb
@@ -36,7 +36,7 @@ class MeetingContent < ActiveRecord::Base
                 url: Proc.new { |o| { controller: '/meetings', action: 'show', id: o.meeting } }
 
   User.before_destroy do |user|
-    MeetingContent.update_all ['author_id = ?', DeletedUser.first], ['author_id = ?', user.id]
+    MeetingContent.where(['author_id = ?', user.id]).update_all ['author_id = ?', DeletedUser.first]
   end
 
   def editable?
diff --git a/app/models/meeting_participant.rb b/app/models/meeting_participant.rb
index 45de9ff604..726abf39a5 100644
--- a/app/models/meeting_participant.rb
+++ b/app/models/meeting_participant.rb
@@ -28,7 +28,7 @@ class MeetingParticipant < ActiveRecord::Base
   attr_accessible :email, :name, :invited, :attended, :user, :user_id, :meeting
 
   User.before_destroy do |user|
-    MeetingParticipant.update_all ['user_id = ?', DeletedUser.first], ['user_id = ?', user.id]
+    MeetingParticipant.where(['user_id = ?', user.id]).update_all ['user_id = ?', DeletedUser.first]
   end
 
   def name