config.load_defaults is now 7.1 and I had to add optional belongs to to a couple models as a deprecation from the 4.2 to 5.0 upgrade

app/models/application_record.rb

@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+    self.abstract_class = true
+end

app/models/mat.rb

@@ -1,4 +1,4 @@
-class Mat < ActiveRecord::Base
+class Mat < ApplicationRecord
 	belongs_to :tournament
 	has_many :matches
 

app/models/match.rb

@@ -1,7 +1,7 @@
-class Match < ActiveRecord::Base
+class Match < ApplicationRecord
 	belongs_to :tournament, touch: true
 	belongs_to :weight, touch: true
-	belongs_to :mat, touch: true
+	belongs_to :mat, touch: true, optional: true
 	has_many :wrestlers, :through => :weight
 	has_many :schools, :through => :wrestlers
 	validate :score_validation, :win_type_validation, :bracket_position_validation, :overtime_type_validation

app/models/school.rb

@@ -1,4 +1,4 @@
-class School < ActiveRecord::Base
+class School < ApplicationRecord
 	belongs_to :tournament, touch: true
 	has_many :wrestlers, dependent: :destroy
 	has_many :deductedPoints, class_name: "Teampointadjust"

app/models/school_delegate.rb

@@ -1,4 +1,4 @@
-class SchoolDelegate < ActiveRecord::Base
+class SchoolDelegate < ApplicationRecord
     belongs_to :school
     belongs_to :user
 end

app/models/teampointadjust.rb

@@ -1,6 +1,6 @@
-class Teampointadjust < ActiveRecord::Base
-    belongs_to :wrestler, touch: true
-    belongs_to :school, touch: true
+class Teampointadjust < ApplicationRecord
+    belongs_to :wrestler, touch: true, optional: true
+    belongs_to :school, touch: true, optional: true
     
     after_save do
         advance_wrestlers_and_calc_team_score

app/models/tournament.rb

@@ -1,6 +1,6 @@
-class Tournament < ActiveRecord::Base
+class Tournament < ApplicationRecord
 
-	belongs_to :user
+	belongs_to :user, optional: true
 	has_many :schools, dependent: :destroy
 	has_many :weights, dependent: :destroy
 	has_many :mats, dependent: :destroy

app/models/tournament_delegate.rb

@@ -1,4 +1,4 @@
-class TournamentDelegate < ActiveRecord::Base
+class TournamentDelegate < ApplicationRecord
     belongs_to :tournament
     belongs_to :user
 end

app/models/user.rb

@@ -1,4 +1,4 @@
-class User < ActiveRecord::Base
+class User < ApplicationRecord
   # Include default devise modules. Others available are:
   # :confirmable, :lockable, :timeoutable and :omniauthable
   has_many :tournaments

app/models/weight.rb

@@ -1,5 +1,5 @@
-class Weight < ActiveRecord::Base
-	belongs_to :tournament
+class Weight < ApplicationRecord
+	belongs_to :tournament, touch: true
 	has_many :wrestlers, dependent: :destroy
 	has_many :matches, dependent: :destroy
 

app/models/wrestler.rb

@@ -1,4 +1,4 @@
-class Wrestler < ActiveRecord::Base
+class Wrestler < ApplicationRecord
 	belongs_to :school, touch: true
 	belongs_to :weight, touch: true
 	has_one :tournament, through: :weight