Summary: | 近年來由於全球資訊網的盛行,造成網際網路上的資料需求量大增,資料庫管理系統與全球資訊網必須結合以滿足客戶端的資訊需求。但隨著網路異質性的增加,不同的平台、作業系統及通訊協定不斷地加入使用,不一致的問題亦隨之而來。
同時,物件資料庫的兩大標準,SQL3與ODMG,在許多觀念上不儘相同。因此,本研究嘗試從物件模型及查詢語言兩方面著手,以物件觀點來分析兩者的相同及相異處,提出一對應模式,並實做一個資料庫中介系統,以轉換兩種語言在語法上的差異。
=== In recent years, the complexity of database systems has been enhanced under the development of client/server architecture and distributed computing systems. Usually this type of system combines different hardware, network protocols or DBMSs.
Because the Internet and WWW are more and more popular, many people regard "Network as a computer" or "Network as a global database." It is obvious heterogeneous databases will be connected via WWW in order to provide more information. In the meantime, new OODBMS standards, SQL3 and ODMG, are emerging. Although the two standards both support for object facilities, they are quite different in object model and query languages. Therefore, the mapping between these two standards is necessary. We propose a comparison model and develop an experimental gateway according to the model.
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