diff --git a/activerecord/lib/active_record/tasks/database_tasks.rb b/activerecord/lib/active_record/tasks/database_tasks.rb
index 0883e80d23..d8e0cd1e30 100644
--- a/activerecord/lib/active_record/tasks/database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/database_tasks.rb
@@ -315,12 +315,16 @@ module ActiveRecord
           environments << "test" if environment == "development"
 
           ActiveRecord::Base.configurations.slice(*environments).each do |configuration_environment, configuration|
+            next unless configuration["database"]
+
             yield configuration, configuration_environment
           end
         end
 
         def each_local_configuration
           ActiveRecord::Base.configurations.each_value do |configuration|
+            next unless configuration["database"]
+
             if local_database?(configuration)
               yield configuration
             else
diff --git a/activerecord/test/cases/tasks/database_tasks_test.rb b/activerecord/test/cases/tasks/database_tasks_test.rb
index da7ca27f13..21226352ff 100644
--- a/activerecord/test/cases/tasks/database_tasks_test.rb
+++ b/activerecord/test/cases/tasks/database_tasks_test.rb
@@ -124,6 +124,14 @@ module ActiveRecord
       ActiveRecord::Base.connection_handler.stubs(:establish_connection)
     end
 
+    def test_ignores_configurations_without_databases
+      @configurations["development"].merge!("database" => nil)
+
+      ActiveRecord::Tasks::DatabaseTasks.expects(:create).never
+
+      ActiveRecord::Tasks::DatabaseTasks.create_all
+    end
+
     def test_ignores_remote_databases
       @configurations["development"].merge!("host" => "my.server.tld")
       $stderr.stubs(:puts).returns(nil)
@@ -242,6 +250,14 @@ module ActiveRecord
       ActiveRecord::Base.stubs(:configurations).returns(@configurations)
     end
 
+    def test_ignores_configurations_without_databases
+      @configurations[:development].merge!("database" => nil)
+
+      ActiveRecord::Tasks::DatabaseTasks.expects(:drop).never
+
+      ActiveRecord::Tasks::DatabaseTasks.drop_all
+    end
+
     def test_ignores_remote_databases
       @configurations[:development].merge!("host" => "my.server.tld")
       $stderr.stubs(:puts).returns(nil)
diff --git a/railties/lib/rails/application/configuration.rb b/railties/lib/rails/application/configuration.rb
index 8af364f1e4..b42ffe50d8 100644
--- a/railties/lib/rails/application/configuration.rb
+++ b/railties/lib/rails/application/configuration.rb
@@ -179,7 +179,6 @@ module Rails
               values.reverse_merge!(shared)
             end
           end
-          loaded_yaml.delete("default")
           Hash.new(shared).merge(loaded_yaml)
         elsif ENV["DATABASE_URL"]
           # Value from ENV['DATABASE_URL'] is set to default database connection