diff --git a/.gitignore b/.gitignore
index e9cd89e..50a350e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,5 @@
+*.log
+.byebug_history
 /.bundle/
 /.yardoc
 /Gemfile.lock
diff --git a/.travis.yml b/.travis.yml
index 22437a4..9f67a52 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,6 +7,16 @@ rvm:
   - 2.3.4
   - 2.4.1
 
+env:
+  - DB=sqlite
+  - DB=postgresql
+  - DB=mysql
+
+services:
+  - mysql
+addons:
+  postgresql: "9.3"
+
 gemfile:
   - gemfiles/rails_4.gemfile
   - gemfiles/rails_5.gemfile
diff --git a/acts_as_votable.gemspec b/acts_as_votable.gemspec
index 55823f3..e109999 100644
--- a/acts_as_votable.gemspec
+++ b/acts_as_votable.gemspec
@@ -24,6 +24,8 @@ Gem::Specification.new do |s|
 
   s.add_development_dependency "rspec", "~> 3.6"
   s.add_development_dependency "sqlite3", "~> 1.3"
+  s.add_development_dependency "mysql2", "~> 0.4"
+  s.add_development_dependency "pg", "~> 0.15"
   s.add_development_dependency "rubocop", "~> 0.49.1"
   s.add_development_dependency "simplecov", "~> 0.15.0"
   s.add_development_dependency "appraisal", "~> 2.2"
diff --git a/spec/shared_example/votable_model.rb b/spec/shared_example/votable_model.rb
index da4d290..79985c1 100644
--- a/spec/shared_example/votable_model.rb
+++ b/spec/shared_example/votable_model.rb
@@ -406,7 +406,7 @@
 
           it do
             expect(votable_cache.cached_votes_total).to eq(1)
-            expect(votable_cache.updated_at).to_not eq updated_at
+            expect(votable_cache.updated_at.to_i).to_not eq(updated_at.to_i)
           end
         end
 
@@ -415,7 +415,7 @@
 
           it do
             expect(votable_cache.cached_votes_total).to eq(1)
-            expect(votable_cache.updated_at).to eq updated_at
+            expect(votable_cache.updated_at.to_i).to eq(updated_at.to_i)
           end
         end
       end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index a261405..3b4ec85 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,139 +1,13 @@
 # frozen_string_literal: true
 
 $LOAD_PATH << File.join(File.dirname(__FILE__), "..", "lib")
-require "sqlite3"
+
 require "simplecov"
 require "acts_as_votable"
 require "factory_girl"
+require_relative "support/database"
 
 Dir["./spec/shared_example/**/*.rb"].sort.each { |f| require f }
 Dir["./spec/support/**/*.rb"].sort.each { |f| require f }
 
 SimpleCov.start
-
-ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
-
-ActiveRecord::Schema.define(version: 1) do
-  create_table :votes do |t|
-    t.references :votable, polymorphic: true
-    t.references :voter, polymorphic: true
-
-    t.boolean :vote_flag
-    t.string :vote_scope
-    t.integer :vote_weight
-
-    t.timestamps
-  end
-
-  add_index :votes, [:votable_id, :votable_type]
-  add_index :votes, [:voter_id, :voter_type]
-  add_index :votes, [:voter_id, :voter_type, :vote_scope]
-  add_index :votes, [:votable_id, :votable_type, :vote_scope]
-
-  create_table :voters do |t|
-    t.string :name
-  end
-
-  create_table :not_voters do |t|
-    t.string :name
-  end
-
-  create_table :votables do |t|
-    t.string :name
-  end
-
-  create_table :votable_voters do |t|
-    t.string :name
-  end
-
-  create_table :sti_votables do |t|
-    t.string :name
-    t.string :type
-  end
-
-  create_table :sti_not_votables do |t|
-    t.string :name
-    t.string :type
-  end
-
-  create_table :not_votables do |t|
-    t.string :name
-  end
-
-  create_table :votable_caches do |t|
-    t.string :name
-    t.integer :cached_votes_total
-    t.integer :cached_votes_score
-    t.integer :cached_votes_up
-    t.integer :cached_votes_down
-    t.integer :cached_weighted_total
-    t.integer :cached_weighted_score
-    t.float :cached_weighted_average
-
-    t.integer :cached_scoped_test_votes_total
-    t.integer :cached_scoped_test_votes_score
-    t.integer :cached_scoped_test_votes_up
-    t.integer :cached_scoped_test_votes_down
-    t.integer :cached_scoped_weighted_total
-    t.integer :cached_scoped_weighted_score
-    t.float :cached_scoped_weighted_average
-
-    t.timestamps
-  end
-
-end
-
-
-class Voter < ActiveRecord::Base
-  acts_as_voter
-end
-
-class NotVoter < ActiveRecord::Base
-end
-
-class Votable < ActiveRecord::Base
-  acts_as_votable
-  validates_presence_of :name
-end
-
-class VotableVoter < ActiveRecord::Base
-  acts_as_votable
-  acts_as_voter
-end
-
-class StiVotable < ActiveRecord::Base
-  acts_as_votable
-end
-
-class ChildOfStiVotable < StiVotable
-end
-
-class StiNotVotable < ActiveRecord::Base
-  validates_presence_of :name
-end
-
-class ChildOfStiNotVotable < StiNotVotable
-  acts_as_votable
-end
-
-class NotVotable < ActiveRecord::Base
-end
-
-class VotableCache < ActiveRecord::Base
-  acts_as_votable
-  validates_presence_of :name
-end
-
-class VotableCacheUpdateAttributes < VotableCache
-  acts_as_votable cacheable_strategy: :update_attributes
-end
-
-class VotableCacheUpdateColumns < VotableCache
-  acts_as_votable cacheable_strategy: :update_columns
-end
-
-class ABoringClass
-  def self.hw
-    "hello world"
-  end
-end
diff --git a/spec/support/database.rb b/spec/support/database.rb
new file mode 100644
index 0000000..438bc5e
--- /dev/null
+++ b/spec/support/database.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+require "logger"
+require "yaml"
+
+ActiveRecord::Base.configurations = YAML.load_file(File.expand_path("db/database.yml", __dir__))
+db_config = ActiveRecord::Base.configurations.fetch(ENV["DB"] || "sqlite")
+
+begin
+  ActiveRecord::Base.establish_connection(db_config)
+  ActiveRecord::Base.connection
+rescue
+  ActiveRecord::Base.establish_connection(db_config.merge("database" => nil))
+  ActiveRecord::Base.connection.create_database(db_config["database"], db_config)
+  ActiveRecord::Base.establish_connection(db_config)
+end
+
+ActiveRecord::Base.logger = Logger.new(File.join(__dir__, "debug.log"))
+ActiveRecord::Base.logger.level = ENV["CI"] ? ::Logger::ERROR : ::Logger::DEBUG
+ActiveRecord::Migration.verbose = false
diff --git a/spec/support/db/database.yml b/spec/support/db/database.yml
new file mode 100644
index 0000000..bb69ac4
--- /dev/null
+++ b/spec/support/db/database.yml
@@ -0,0 +1,16 @@
+sqlite:
+  adapter: sqlite3
+  database: ":memory:"
+
+postgresql:
+  adapter: postgresql
+  username: postgres
+  password:
+  database: acts_as_votable_test
+
+mysql:
+  adapter: mysql2
+  host: localhost
+  username: root
+  password:
+  database: acts_as_votable_test
diff --git a/spec/support/db/schema.rb b/spec/support/db/schema.rb
new file mode 100644
index 0000000..f41e939
--- /dev/null
+++ b/spec/support/db/schema.rb
@@ -0,0 +1,70 @@
+# frozen_string_literal: true
+
+ActiveRecord::Schema.define(version: 1) do
+  create_table :votes, force: true do |t|
+    t.references :votable, polymorphic: true
+    t.references :voter, polymorphic: true
+
+    t.boolean :vote_flag
+    t.string :vote_scope
+    t.integer :vote_weight
+
+    t.timestamps(null: false, precision: 6)
+  end
+
+  add_index :votes, [:votable_id, :votable_type]
+  add_index :votes, [:voter_id, :voter_type]
+  add_index :votes, [:voter_id, :voter_type, :vote_scope]
+  add_index :votes, [:votable_id, :votable_type, :vote_scope]
+
+  create_table :voters, force: true do |t|
+    t.string :name
+  end
+
+  create_table :not_voters, force: true do |t|
+    t.string :name
+  end
+
+  create_table :votables, force: true do |t|
+    t.string :name
+  end
+
+  create_table :votable_voters, force: true do |t|
+    t.string :name
+  end
+
+  create_table :sti_votables, force: true do |t|
+    t.string :name
+    t.string :type
+  end
+
+  create_table :sti_not_votables, force: true do |t|
+    t.string :name
+    t.string :type
+  end
+
+  create_table :not_votables, force: true do |t|
+    t.string :name
+  end
+
+  create_table :votable_caches, force: true do |t|
+    t.string :name
+    t.integer :cached_votes_total
+    t.integer :cached_votes_score
+    t.integer :cached_votes_up
+    t.integer :cached_votes_down
+    t.integer :cached_weighted_total
+    t.integer :cached_weighted_score
+    t.float :cached_weighted_average
+
+    t.integer :cached_scoped_test_votes_total
+    t.integer :cached_scoped_test_votes_score
+    t.integer :cached_scoped_test_votes_up
+    t.integer :cached_scoped_test_votes_down
+    t.integer :cached_scoped_weighted_total
+    t.integer :cached_scoped_weighted_score
+    t.float :cached_scoped_weighted_average
+
+    t.timestamps(null: false, precision: 6)
+  end
+end
diff --git a/spec/support/models.rb b/spec/support/models.rb
new file mode 100644
index 0000000..c4ec9a1
--- /dev/null
+++ b/spec/support/models.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+class Voter < ActiveRecord::Base
+  acts_as_voter
+end
+
+class NotVoter < ActiveRecord::Base
+end
+
+class Votable < ActiveRecord::Base
+  acts_as_votable
+  validates_presence_of :name
+end
+
+class VotableVoter < ActiveRecord::Base
+  acts_as_votable
+  acts_as_voter
+end
+
+class StiVotable < ActiveRecord::Base
+  acts_as_votable
+end
+
+class ChildOfStiVotable < StiVotable
+end
+
+class StiNotVotable < ActiveRecord::Base
+  validates_presence_of :name
+end
+
+class ChildOfStiNotVotable < StiNotVotable
+  acts_as_votable
+end
+
+class NotVotable < ActiveRecord::Base
+end
+
+class VotableCache < ActiveRecord::Base
+  acts_as_votable
+  validates_presence_of :name
+end
+
+class VotableCacheUpdateAttributes < VotableCache
+  acts_as_votable cacheable_strategy: :update_attributes
+end
+
+class VotableCacheUpdateColumns < VotableCache
+  acts_as_votable cacheable_strategy: :update_columns
+end
+
+class ABoringClass
+  def self.hw
+    "hello world"
+  end
+end