示例为对一地下管线数据库的操作，程序对数据内容进行了一定的修改，提高了效率，可作为对该数据库操作的入门程序。-example of a pair of underground pipeline database, the operation procedures of the data content of some modification, increased efficiency, as this data base entry procedures.

CAD管线标注,针对地下管线的属性标注问题-CAD pipeline marked for underground pipeline attribute tagging problem