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lications 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 maliciousintent. The second weakness of manv of the PCbasedsystems is that of performance. If data volumes growup to a few thousands of records, performance couldbe a bottleneck. For anization where growth in data volumesis expected, availability of, the same or patiblesoftware on large machines should be considered. This is one of the most mon misconceptionsabout database management systems that are used inpersonal puters. Thoroughly prehensive andsophisticated business systems can be developed indBASh, Paradox and other DBMSs. However, theyare created by experienced programmers using theDBMS39。 it also frequently uses “information system” instead of “MIS” to refer to an anizational information system. A definition of a management information system, as the term is generally understood, is an integrated, usermachine system for providing information to support operations, management, and decisionmaking functions in an anization. The system utilizes puter hardware and software。 models for analysis planning, control and decision making。 rather, it means that the parts fit into an overall design. The elements of the definition are highlighted below. Computerbased usermachine system Conceptually, a management information can exist without puter, but it is the power of the puter which makes MIS feasible. The question is not whether puters should be used in management information system, but the extent to which information use should be puterized. The concept of a usermachine system implies that some tasks are best performed by humans, while others are best done by machine. The user of an MIS is any person responsible for entering input data, instructing the system, or utilizing the information output of the system. For many problems, the user and the puter form a bined system with results obtained through a set of interactions between the puter and the user. Usermachine interaction is facilitated by operation in which the user’s inputoutput device( usually a visual display terminal) is connected to the puter. The puter can be a personal puter serving only one user or a large puter that serves a number of users through terminals connected by munication lines. The user inputoutput device permits direct input of data and immediate output of results. For instance, a person using the puter interactively in financial planning poses “what if” questions by entering input at the terminal keyboard。 some understanding of puters, the nature of information, and its use in various management function aids users in this task. Integrated system 集成系統(tǒng) Management information system typically provide the basis for integration of anizational 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