Lect2_DataflowSys软件体系结构-PPT讲稿-汉语稿.ppt

? 数据流风格软件体系结构概述 2. 顺序批处理架构 实例1: 更新商店的数据库的批处理系统 对于每天形成的数据盘D1，进行第一次批处理Validate，目的是确保数据格式正确，挑选出来格式有错误的记录，并将所有格式正确的记录写入数据盘D2 接下来的处理要对D2中的内容进行排序，形成新的数据盘D3 最后将D3的内容插入已经存在的数据盘D4 Television $3800 Japan 95-12-11 Television $3600 Germany 88-12-01 Microwave $3800 Japan 95-12-11 Microwave $3600 Germany 88-12-01 Television $3800 Republic of China 95-12-11 Television $3300 Germany 89-02-01 Microwave $3800 Republic of China 95-12-11 Microwave $3300 Germany 89-02-01 Washing Machine $3800 Japan 95-12-11 Washing Machine $3600 Germany 88-12-01 Television $3800 Republic of China 95-12-11 Television $3300 Germany 89-02-01 Washing Machine $3800 Republic of China 95-12-11 Washing Machine $3300 Germany 89-02-01 Television $3800 Japan 1995-12-11 Television $3600 Germany 1988-12-01 Microwave $3800 Japan 1995-12-11 Microwave $3600 Germany 1988-12-01 Television $3800 Republic of China 1995-12-11 Television $3300 Germany 1989-02-01 Microwave $3800 Republic of China 1995-12-11 Microwave $3300 Germany 1989-02-01 Washing Machine $3800 Japan 1995-12-11 Washing Machine $3600 Germany 1988-12-01 Television $3800 Republic of China 1995-12-11 Television $3300 Germany 1989-02-01 Washing Machine $3800 Republic of China 1995-12-11 Washing Machine $3300 Germany 1989-02-01 Television $3800 Japan 1995-12-11 Television $3600 Germany 1988-12-01 Microwave $3800 Japan 1995-12-11 Microwave $3600 Germany 1988-12-01 Television $3800 Taiwan 1995-12-11 Television $3300 Germany 1989-02-01 Microwave $3800 Taiwan 1995-12-11 Microwave $3300 Germany 1989-02-01 Washing Machine $3800 Japan 1995-12-11 Washing Machine $3600 Germany 1988-12-01 Television $3800 Taiwan 1995-12-11 Television $3300 Germany 1989-02-01 Washing Machine $3800 Taiwan 1995-12-11 Washing Machine $3300 Germany 1989-02-01 面临的技术压力: 在线存取(Online Access) 在线存取的优势: 查询更为容易 实时事务处理 要实现在线更新需要由纯批处理方式向交互式处理方式转换 过滤器的功能: 渐增式地将输入数据转换为输出数据，可能为如下几种形式： 通过计算或添加信息丰富数据 改变数据的表示形式 流到流之间的转换 其他… 过滤器的分类： 主动过滤器：主动从管道拉入(pull)数据或推出(push)数据 被动过滤器：数据流动由管道负责推动