common.pkg_com_util.sub_log 写日志讲解

请教下一些语句的解释及用法：common.pkg_com_util.sub_log('INFO',
                         '测试',
                         '测试',
                         'edw01',
                         sysdate,
                         sysdate,
                         sysdate,
                         0,
                         '测试...1 开始...');