diff --git a/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php b/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
index 3631cdf..6452b78 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
@@ -216,6 +216,55 @@
 	// --------------------------------------------------------------------
 
 	/**
+	 * Begin Transaction
+	 *
+	 * @return	bool
+	 */
+	protected function _trans_begin()
+	{
+		$this->conn_id->setAttribute(PDO::ATTR_AUTOCOMMIT, FALSE);
+		return $this->conn_id->beginTransaction();
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Commit Transaction
+	 *
+	 * @return	bool
+	 */
+	protected function _trans_commit()
+	{
+		if ($this->conn_id->commit())
+		{
+			$this->conn_id->setAttribute(PDO::ATTR_AUTOCOMMIT, TRUE);
+			return TRUE;
+		}
+
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Rollback Transaction
+	 *
+	 * @return	bool
+	 */
+	protected function _trans_rollback()
+	{
+		if ($this->conn_id->rollBack())
+		{
+			$this->conn_id->setAttribute(PDO::ATTR_AUTOCOMMIT, TRUE);
+			return TRUE;
+		}
+
+		return FALSE;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
 	 * Show table query
 	 *
 	 * Generates a platform-specific query string so that the table names can be fetched
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index d99e442..d41e799 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -27,6 +27,7 @@
 -  Fixed a bug (#4805) - :doc:`Database <database/index>` driver 'mysqli' didn't use the ``MYSQLI_CLIENT_SSL_DONT_VERIFY_SERVER_CERT`` flag properly.
 -  Fixed a bug (#4808) - :doc:`Database <database/index>` method ``is_write_type()`` only looked at the first line of a queries using ``RETURNING`` with the 'postgre', 'pdo/pgsql', 'odbc' and 'pdo/odbc' drivers.
 -  Fixed a bug where :doc:`Query Builder <database/query_builder>` method ``insert_batch()`` tried to execute an unsupported SQL query with the 'ibase' and 'pdo/firebird' drivers.
+-  Fixed a bug (#4809) - :doc:`Database <database/index>` driver 'pdo/mysql' didn't turn off ``AUTOCOMMIT`` when starting a transaction.
 
 Version 3.1.0
 =============