【正文】 cation programs are customized for each data entry and updating function. Software for personal puters which perform me of the DBMS functions have been very popular. Personal puters were intended for use by individuals for personal information storage and process These machines have also been used extensively small enterprises, professionals like doctors, acrylics, engineers, lawyers and so on .By the nature of intended 6 usage, database systems on these machines except from several of the requirements of full doge database systems. Since data sharing is not tended, concurrent operations even less so, the fewer can be less plex. Security and integrity maintenance are deemphasized or absent. As data limes will be small, performance efficiency is also important. In fact, the only aspect of a database system that is important is data Independence. Datadependence, as stated earlier, means that applicant programs and user queries need not recognizant physical organization of data on secondary storage. The importance of this aspect, particularly for the personal puter user, is that this greatly simplifies database usage. The user can store, access and manipulate data at a high level (close to the application) and be totally shielded from the low level (close to the machine) details of data organization. We will not discuss details of specific PC DBMS software packages here. Let us summarize in the following the strengths and weaknesses of personal puter database software systems： The most obvious positive factor is the user friendliness of the software. A user with no prior puter background would be able to use the system to store personal and professional data, retrieve and perform relayed processing. The user should, of course, satiety himself about the quality of software and the freedom from errors (bugs) so that investmerits in data arc protected. For the programmer implementing applications with them, the advantage lies in the support for applications development in terms of input screen generations, output report generation etc. offered by theses stems. The main negative point concerns absence of data protection features. Unless encrypted, data cane accessed by whoever has access to the machine Data can be destroyed through mistakes or malicious intent. The second weakness of many of the PCbased systems is that of performance. If data volumes grow up to a few thousands of records, performance could be a bottleneck. For organization where growth in data volumes is expected, availability of, the same or patible software on large machines should be considered. This is one of the most mon misconceptions about database management systems that are used in personal puters. Thoroughly prehensive and sophisticated business systems can be developed in dBASE, Paradox and other DBMSs. However, they are created by experienced programmers using the DBMS39。 models for analysis planning, control and decision making。 some understanding of puters, the nature of information, and its use in various management function aids users in this task. Management information system typically provide the basis for integration of 9 organizational information processing. Individual applications within information systems are developed for and by diverse sets of users. If there are no integrating processes and mechanisms, the individual applications may be inconsistent and inpatible. Data item may be specified differently and may not be patible across applications that use the same data. There may be redundant development of separate applications when actually a single application could serve more than one need. A user wanting to perform analysis using data from two different applications may find the task very difficult and sometimes impossible. The first step in integration of information system applications is an overall information system plan. Even though application systems are implemented one at a time, their design can be guided by the overall plan, which determines how they fit in with other functions. In essence, the information system is designed as a planed federation of small systems. Information system integration is also achieved through standards, guidelines, and procedures set by the MIS function. The enforcement of such standards and procedures permit diverse applications to share data, meet audit and control requirements, and be shares by multiple users. For instance, an application may be developed to run on a particular small puter. Standards for integration may dictate that the equipment selected be patible with the centralized database. The trend in information system design is toward separate application processing form the data used to support it. The separate database is the mechanism by which data items are integrated across many applications and made consistently available to a variety of users. The need for a database in MIS is discussed below. The term “information” and “data” are frequently used interchangeably。 數(shù)據(jù)庫本身不是什么新鮮事 —— 早期的數(shù)據(jù)庫鑿在石頭上 ， 記在名冊上 ， 以及寫在索引卡中 。DBMS 軟件包中的程序在數(shù)據(jù)庫與其用戶間建立接口 。 這些問題最初可能是模糊的并且（或者）是定義不恰當?shù)?， 但是人們可以瀏覽數(shù)據(jù)庫直到獲得所需的信 息 。 然而 ， DBMS 的可用性為用戶提供了一個更快的替代通信通道 。 當前 ， 執(zhí)行數(shù)據(jù)庫系的一些功能的個人計算機軟件一直很流行 。 由于不需要數(shù)據(jù)分享 ， 也不需要同時操作 。 正如以前所述 ， 數(shù)據(jù)獨立是指在輔助存儲器上 ， 應用程序和用戶詢問不必知道數(shù)排的物理組織 。 我們將在下面總結一下個人計算機數(shù)據(jù)庫軟件系統(tǒng)的優(yōu)缺點： 最明顯的積極方面是軟件的用戶友好型 。 主要消極點是缺少數(shù)據(jù)保護特征 。 如果數(shù)據(jù)發(fā)展到幾千個記錄 ， 效率問題可能是一個難關 。 數(shù)據(jù)庫的業(yè)務管理 長期業(yè)務的目的是：在應用環(huán)境中模擬長期的、相互作用的數(shù)據(jù)庫存取對話傳統(tǒng)業(yè)務模式中關于短期業(yè)務的基本假設對于長期業(yè)務是不適用的 。 在傳統(tǒng)業(yè)務中采取的一致性標準是一種串行概念 。 數(shù)據(jù)庫的文本管理 在計算機輔助設計和軟件工程的 環(huán)境影響下 ， 盡管對本文支持有許多建議 ， 但對本文語義的意見不一致一直大大妨礙了數(shù)據(jù)庫系統(tǒng)的文本支持 。 從廣義上說 ， 在文本的研究和發(fā)展方面有三個方向 。 第三個方向是對語義進行研究并執(zhí)行描述一大批物體和數(shù)據(jù)庫的構圖 。 一個管理信息系統(tǒng)的定義 ， 通常被理解為：一種集成用戶機器系統(tǒng) ， 為組織提供信息支持運作、管理、決策職能 。 理論上 ， 管理信息系統(tǒng)可以脫離計算機上而存在 ， 但是計算機的存在可以讓管理信 息系統(tǒng)可行 。 因為許多問題 ，用戶和計算機建立了一個聯(lián)合系統(tǒng) ， 其結果通過一套在計算機和用戶之間的相互作用得