以XML與Web服務建立一個資訊共用機制

Abstract

資料的重複儲存，是一直困擾著資料庫管理者的一個項老問題，它主要會造成兩項問題：（1）耗費儲存體空間，（2）資料更新困難，造成資料老舊、不正確。 而資料取用的不方便，往往造成資料的必須重複輸入，耗時又易產生錯誤。我們在網頁上填寫表格時，一再的填寫姓名、住址、電子信箱等資料就是明顯的例子。 如何能將資料以簡易而標準的形式儲存，如何能隨時隨地很方便的取得資料，是我們探討的目標。 在本論文中我們嘗試以XML來作為資料儲存的格式。理由是它是公認最有彈性的格式，已為各行各業所採用，在所有平台上都有許多現成的工具來處理它。它已經是一項標準格式，不需設計直接可用。 另外，我們採用微軟的Web Service架構來建立資料的方便性。主要理由有二：（1）只要能連上網路，不管在世界上哪一個角落都可取得存好的資料。（2）在此架構下，程式間都以XML形式交還資料，因此在用戶端可以用任何平台、任何語言來設計，不會有平台的限制。 我們也實做了一個試驗性的系統，驗證這些想法，初步證實了其實用價值。

The redundancy of data storage has been an old problem for database administrators. It incurs two obvious problems:(1) waste of storage capacity, and (2) difficulty in data updates, resulting in obsolete data. On the other hand, low accessibility of data often results in repeated key-in of data. When we fill forms on webs, we enter our name, residence address, e-mail address, etc. over and over again. The goal of this thesis is to investigate how to store data in a standard format and make it highly accessible. In this thesis, we try to use XML format for the storage of data. XML has proved itself the most flexible format for all sorts of business and has been accepted by all professions. There are more and more tools to process it on all platforms. We also try to make use of Web Service of Microsoft to set up the accesibility of data, for two good reasons:(1)With Web Service, we can access data from all over the world as long as we are connected to Internet; (2)On Web Service, all data are exchanged theough XML. On the client side, interface can be implemented in any language, on any platform. We have implemented a pilot system, which has validated all our ideas.