Remove need for using alias_method trick using the inheritance

That trick make the code hard to understand, this implementation is
more readable.

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -196,14 +196,7 @@ def disable_referential_integrity # :nodoc:
 
       # Executes the SQL statement in the context of this connection.
       def execute(sql, name = nil, async: false)
-        materialize_transactions
-        mark_transaction_written_if_write(sql)
-
-        log(sql, name, async: async) do
-          ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
-            @connection.query(sql)
-          end
-        end
+        raw_execute(sql, name, async)
       end
 
       # Mysql2Adapter doesn't have to free a result after using it, but we use this method
@@ -629,6 +622,17 @@ def type_map
           emulate_booleans ? TYPE_MAP_WITH_BOOLEAN : TYPE_MAP
         end
 
+        def raw_execute(sql, name, async: false)
+          materialize_transactions
+          mark_transaction_written_if_write(sql)
+
+          log(sql, name, async: async) do
+            ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+              @connection.query(sql)
+            end
+          end
+        end
+
         # See https://dev.mysql.com/doc/mysql-errors/en/server-error-reference.html
         ER_DB_CREATE_EXISTS     = 1007
         ER_FILSORT_ABORT        = 1028

activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb

@@ -37,16 +37,6 @@ def explain(arel, binds = [])
           MySQL::ExplainPrettyPrinter.new.pp(result, elapsed)
         end
 
-        def execute(sql, name = nil, async: false)
-          # make sure we carry over any changes to ActiveRecord.default_timezone that have been
-          # made since we established the connection
-          @connection.query_options[:database_timezone] = ActiveRecord.default_timezone
-
-          super
-        end
-        alias_method :raw_execute, :execute
-        private :raw_execute
-
         # Executes the SQL statement in the context of this connection.
         def execute(sql, name = nil, async: false)
           sql = transform_query(sql)
@@ -91,6 +81,14 @@ def exec_delete(sql, name = nil, binds = []) # :nodoc:
         alias :exec_update :exec_delete
 
         private
+          def raw_execute(sql, name, async: false)
+            # make sure we carry over any changes to ActiveRecord.default_timezone that have been
+            # made since we established the connection
+            @connection.query_options[:database_timezone] = ActiveRecord.default_timezone
+
+            super
+          end
+
           def execute_batch(statements, name = nil)
             statements = statements.map { |sql| transform_query(sql) }
             combine_multi_statements(statements).each do |statement|