計(jì)算機(jī)專業(yè)外文翻譯---dbms和mis

1、<p>　　眾所周知，數(shù)據(jù)庫(kù)是邏輯上相關(guān)的數(shù)據(jù)元的匯集。這些數(shù)據(jù)元可以按不同的結(jié)構(gòu)組織起來(lái)，以滿足單位和個(gè)人的多種處理和檢索的需要。數(shù)據(jù)庫(kù)本身不是什么新鮮事—一早期的數(shù)據(jù)庫(kù)鑿在石頭上，記在名冊(cè)上，以及寫在索引卡中。而現(xiàn)在，數(shù)據(jù)庫(kù)普遍記錄在可磁化的介質(zhì)上，并且需要用計(jì)算機(jī)程序來(lái)執(zhí)行必需的存儲(chǔ)和檢索操作。</p><p>　　如下所述，所有數(shù)據(jù)庫(kù)（最簡(jiǎn)單的除外）中都有復(fù)雜的數(shù)據(jù)關(guān)系及其鏈接。處理與創(chuàng)建、訪問(wèn)

2、以及維護(hù)數(shù)據(jù)庫(kù)記錄有關(guān)的復(fù)雜任務(wù)的系統(tǒng)軟件包叫做數(shù)據(jù)庫(kù)管理系統(tǒng)（DBMS）。DBMS軟件包中的程序在數(shù)據(jù)庫(kù)與其用戶間建立接口。（這些用戶可以是應(yīng)用程序員、管理員、及其他需要信息的人員和各種操作系統(tǒng)程序）。</p><p>　　DBMS可組織、處理和表示從數(shù)據(jù)庫(kù)中選出的數(shù)據(jù)元。該功能使決策者能搜索、探查和查詢數(shù)據(jù)庫(kù)的內(nèi)容，從而對(duì)在正規(guī)報(bào)告中沒(méi)有的、不再出現(xiàn)的且無(wú)法預(yù)料的問(wèn)題作出回答。這些問(wèn)題最初可能是模糊的并且（或

3、者）是定義不恰當(dāng)?shù)?，但是人們可以瀏覽數(shù)據(jù)庫(kù)直到獲得所需的信息。簡(jiǎn)言之，DBMS將“管理”存儲(chǔ)的數(shù)據(jù)項(xiàng)，并從公共數(shù)據(jù)庫(kù)中匯集所需的數(shù)據(jù)項(xiàng)以回答非程序員的詢問(wèn)。在面向文件的系統(tǒng)中，需要特定信息的用戶應(yīng)將他們的要求傳送給程序員。該程序員在時(shí)間允許時(shí)，將編寫一個(gè)或多個(gè)程序以提取數(shù)據(jù)和準(zhǔn)備信息。然而，DBMS的可用性為用戶提供了一個(gè)更快的替代通信通道（如圖7-1所示）。</p><p>　　如果數(shù)據(jù)庫(kù)管理系統(tǒng)提供一種方法來(lái)

4、相互作用地進(jìn)入和修改數(shù)據(jù)庫(kù)，同時(shí)查詢數(shù)據(jù)庫(kù)，這種方法就為管理個(gè)人數(shù)據(jù)庫(kù)創(chuàng)造了條件。但是，它不能自動(dòng)留下一串查賬行動(dòng)，也不能在多用戶組織中提供那種必要的控制。只有當(dāng)一套應(yīng)用程序?yàn)槊恳粋€(gè)數(shù)據(jù)進(jìn)入和修改功能設(shè)定客戶規(guī)格時(shí)，才有可能得到這些控制。    </p><p>　　當(dāng)前，執(zhí)行數(shù)據(jù)庫(kù)系的一些功能的個(gè)人計(jì)算機(jī)軟件一直很流行。個(gè)人計(jì)算機(jī)是供個(gè)人信息存儲(chǔ)和處理而用。這些機(jī)器也廣泛

5、地被一些小企業(yè)、職業(yè)家如建筑師，醫(yī)師、工程師、律師等等所使用。從使用意圖的性質(zhì)看，這些機(jī)器上的數(shù)據(jù)庫(kù)系統(tǒng)沒(méi)有正式數(shù)據(jù)庫(kù)系統(tǒng)的一些要求。由于不需要數(shù)據(jù)分享，也不需要同時(shí)操作。軟件也就不那么復(fù)雜。安全和整體維護(hù)也不那么重要，甚至沒(méi)有隨著數(shù)據(jù)容量變性能效率也不那么重要。事實(shí)上，數(shù)據(jù)庫(kù)系統(tǒng)唯一重要的方面是數(shù)據(jù)獨(dú)立。正如以前所述，數(shù)據(jù)獨(dú)立是指在輔助存儲(chǔ)器上，應(yīng)用程序和用戶詢問(wèn)不必知道數(shù)排的物理組織。這個(gè)方面的重要性，尤其對(duì)個(gè)人計(jì)算機(jī)用戶來(lái)說(shuō)，大大

6、簡(jiǎn)化了數(shù)據(jù)庫(kù)的使用。用戶能夠高層次地存儲(chǔ)，存取和操縱數(shù)據(jù)，并且能夠完全不受數(shù)據(jù)組織低層次細(xì)節(jié)的影響。在這里我們將不討論一個(gè)特定個(gè)人計(jì)算機(jī)數(shù)據(jù)庫(kù)管理系統(tǒng)軟件包細(xì)節(jié)。我們將在下面總結(jié)一下個(gè)人計(jì)算機(jī)數(shù)據(jù)庫(kù)軟件系統(tǒng)的優(yōu)缺點(diǎn)： </p><p>　　最明顯的積極方面是軟件的用戶友好型。一個(gè)事先不了解計(jì)算機(jī)知識(shí)的用戶能夠使用該系統(tǒng)來(lái)儲(chǔ)存?zhèn)€人和職業(yè)數(shù)據(jù)，檢索和執(zhí)行有關(guān)處理。當(dāng)然，用戶應(yīng)該使自己對(duì)軟件質(zhì)量感到滿足，高質(zhì)

7、量的軟件仗數(shù)據(jù)的出錯(cuò)率減少?gòu)亩箶?shù)據(jù)投資 得到保護(hù)。</p><p>　　對(duì)于完成應(yīng)用的程序員而言，這個(gè)優(yōu)點(diǎn)存在于支持這些系統(tǒng)所提供的在輸入屏幕產(chǎn)生，輸出報(bào)告產(chǎn)生方面的應(yīng)用發(fā)展。    </p><p>　　主要消極點(diǎn)是缺少數(shù)據(jù)保護(hù)特征。除非被譯成密碼，數(shù)據(jù)不能被任何接觸機(jī)器的人所存取。數(shù)據(jù)也能由于錯(cuò)誤或被懷有惡意的人毀掉。以個(gè)人計(jì)算機(jī)為基礎(chǔ)的許多系

8、 統(tǒng)的第二個(gè)缺點(diǎn)是效率方面的缺點(diǎn)。如果數(shù)據(jù)發(fā)展到幾千個(gè)記錄，效率問(wèn)題可能是一個(gè)難關(guān)。     </p><p>　　由于數(shù)據(jù)容量的增長(zhǎng)是一種發(fā)展趨勢(shì)，所以應(yīng)該考慮在較大的權(quán)器上獲得相同或相容的軟件。    </p><p>　　這是對(duì)用個(gè)人計(jì)算機(jī)數(shù)據(jù)庫(kù)管理系統(tǒng)的最常見的錯(cuò)誤概念之一：高綜合和復(fù)雜的商業(yè)系統(tǒng)可以在

9、dBASE，Paradox和其它數(shù)據(jù)庫(kù)譽(yù)理系統(tǒng)中得以發(fā)展。但是，這些商業(yè)系統(tǒng)是由富有經(jīng)驗(yàn)的程序設(shè)計(jì)員通過(guò)使用數(shù)據(jù)庫(kù)管理系統(tǒng)專用的程序語(yǔ)言而建立的，這與建立和管理不是公司主要系統(tǒng)部分的個(gè)人文件的用戶有所不同。</p><p>　　1. 數(shù)據(jù)庫(kù)的業(yè)務(wù)管理   </p><p>　　長(zhǎng)期業(yè)務(wù)的目的是：在應(yīng)用環(huán)境中模擬長(zhǎng)期的、相互作用的數(shù)據(jù)庫(kù)存取對(duì)話傳統(tǒng)業(yè)務(wù)模式中關(guān)于

10、短期業(yè)務(wù)的基本假設(shè)對(duì)于長(zhǎng)期業(yè)務(wù)是不適用的。在存取數(shù)據(jù)前，當(dāng)交易試圖獲得鎖定時(shí)，傳統(tǒng)模式業(yè)務(wù)的執(zhí)行可能會(huì)引起長(zhǎng)期等待。也可能引起大量工作丟失，當(dāng)交易隨著用戶產(chǎn)生的障礙或系統(tǒng)失靈被放棄時(shí)。     </p><p>　　業(yè)務(wù)模式的目的是提供嚴(yán)格的基礎(chǔ)，在潛系統(tǒng)失靈的情況下，為了保持一套多個(gè)同時(shí)讀寫存取及數(shù)據(jù)庫(kù)一致性，業(yè)務(wù)模式自動(dòng)實(shí)行一個(gè)標(biāo)準(zhǔn)。在傳統(tǒng)業(yè)務(wù)中采取的一致性標(biāo)準(zhǔn)是一種串

11、行概念。在傳統(tǒng)數(shù)據(jù)庫(kù)系統(tǒng)中為自動(dòng)并行控制，通過(guò)使用鎖定而實(shí)行串行，并為了從系統(tǒng)失靈中自動(dòng)恢復(fù)而聯(lián)機(jī)。一個(gè)不能為實(shí)施自動(dòng)數(shù)據(jù)庫(kù)一致性而提供基礎(chǔ)的業(yè)務(wù)不是一個(gè)真業(yè)務(wù)。確切地說(shuō)，一個(gè)長(zhǎng)期業(yè)務(wù)不必非采用串行作為它的一致標(biāo)準(zhǔn)，但是，必須有一些一致性的標(biāo)準(zhǔn)。</p><p>　　2. 數(shù)據(jù)庫(kù)的文本管理     </p><p>　　在計(jì)算機(jī)輔助設(shè)計(jì)和軟件工程的環(huán)

12、境影響下，盡管對(duì)本文支持有許多建議，但對(duì)本文語(yǔ)義的意見不一致一直大大妨礙了數(shù)據(jù)庫(kù)系統(tǒng)的文本支持。由于文件和數(shù)據(jù)庫(kù)之間的差別，從直觀上很清楚數(shù)據(jù)庫(kù)系統(tǒng)的文本模式不可能與文件系統(tǒng)所采用的支持軟件工程的文本模式同樣簡(jiǎn)單。對(duì)于數(shù)據(jù)庫(kù)來(lái)說(shuō)，有必要不僅管理單個(gè)事務(wù)的文本（例如，一個(gè)軟件模塊，一份文件等等）而且也要管理許多事務(wù)（例如一個(gè)復(fù)合文件，一個(gè)用戶手冊(cè)等等）甚至還要管理數(shù)據(jù)庫(kù)構(gòu)圖的文本。（例如一個(gè)表格和或一個(gè)類別，許多表格，許多類別）。

13、0;    </p><p>　　從廣義上說(shuō)，在文本的研究和發(fā)展方面有三個(gè)方向。第一，是參數(shù)文本的概念，即設(shè)計(jì)和任一種文本系統(tǒng)，其行為可能通過(guò)調(diào)節(jié)系統(tǒng)參數(shù)而改制。鑒于對(duì)文本的每一個(gè)單方而有許多似乎可行的選擇這一事實(shí)，這可能是唯一可行的方法。 第二個(gè)方向是重訪文本每一個(gè)方面的可一行的選擇，目的在于將其中或者是不實(shí)用的或者有毛病的選擇丟掉。第三個(gè)方向是對(duì)語(yǔ)義進(jìn)行研究并執(zhí)行描述一大批物體和

14、數(shù)據(jù)庫(kù)的構(gòu)圖。</p><p>　　對(duì)于“管理信息系統(tǒng)”并沒(méi)有一致的定義。一些作者喜歡用其他術(shù)語(yǔ)代替，例如：“信息處理系統(tǒng)”“信息與決策系統(tǒng)”“組織信息系統(tǒng)”，或者干脆將“信息系統(tǒng)”用組織內(nèi)具有支持操作、管理、決策職能的計(jì)算機(jī)信息處理系統(tǒng)代替。這篇文章使用“管理信息系統(tǒng)”一詞，是因?yàn)樗峭ㄋ滓锥?，?dāng)涉及組織信息系統(tǒng)時(shí)也常用“信息系統(tǒng)”代替“管理信息系統(tǒng)”。</p><p>　　一個(gè)管理信

15、息系統(tǒng)的定義，通常被理解為：一種集成用戶機(jī)器系統(tǒng)，為組織提供信息支持運(yùn)作、管理、決策職能。該信息系統(tǒng)利用計(jì)算機(jī)硬件和軟件；手工處理程序；模擬分析法計(jì)劃、控制和決策；和數(shù)據(jù)庫(kù)。事實(shí)上，它是一個(gè)集成系統(tǒng)并不意味著它是單一的，單塊集成結(jié)構(gòu)；相反，它意味著零件適合加入整體設(shè)計(jì)。內(nèi)容定義如下：</p><p>　　計(jì)算機(jī)為主的用戶機(jī)器系統(tǒng)。</p><p>　　理論上，管理信息系統(tǒng)可以脫離計(jì)算機(jī)上而

16、存在，但是計(jì)算機(jī)的存在可以讓管理信息系統(tǒng)可行。問(wèn)題不是計(jì)算機(jī)是否被使用在管理信息系統(tǒng)中，而是信息的使用被計(jì)算機(jī)化的程度。用戶機(jī)器系統(tǒng)的概念暗示了, 一些任務(wù)最好由人執(zhí)行, 其他的最好由機(jī)器做。MIS的使用者是那些負(fù)責(zé)輸入輸入數(shù)據(jù)、指示系統(tǒng)或運(yùn)用系統(tǒng)信息產(chǎn)品的人。因?yàn)樵S多問(wèn)題，用戶和計(jì)算機(jī)建立了一個(gè)聯(lián)合系統(tǒng)，其結(jié)果通過(guò)一套在計(jì)算機(jī)和用戶之間的相互作用得到。</p><p>　　用戶機(jī)器的相互作用是由用戶連接在計(jì)算機(jī)

17、上的輸入-輸出設(shè)備（通常是一個(gè)視覺(jué)顯示終端）推動(dòng)的。計(jì)算機(jī)可以使一臺(tái)個(gè)人機(jī)器服務(wù)于一名用戶或者一臺(tái)大規(guī)模的機(jī)器為一定數(shù)量通過(guò)終端由通信線路連接的用戶服務(wù)。用戶輸入-輸出設(shè)備允許直接輸入數(shù)據(jù)和緊接著輸出結(jié)果。例如：一個(gè)人使用計(jì)算機(jī)交互的在金融理財(cái)上通過(guò)在終端鍵盤輸入提交“如果什么，怎么辦？”之類的問(wèn)題，結(jié)果幾秒鐘后便被顯示在屏幕上。</p><p>　　MIS的計(jì)算機(jī)為主的用戶機(jī)器特征影響系統(tǒng)開發(fā)商和系統(tǒng)用戶的知識(shí)

18、要求。“計(jì)算機(jī)為主”意味著管理信息系統(tǒng)的設(shè)計(jì)者必須擁有計(jì)算機(jī)和對(duì)處理有用的知識(shí)?！坝脩魴C(jī)器”的概念意味著系統(tǒng)設(shè)計(jì)者也應(yīng)該了解人作為系統(tǒng)組成部分（信息處理器）的能力和人作為信息使用者的行為。</p><p>　　信息系統(tǒng)的應(yīng)用不應(yīng)該要求用戶成為計(jì)算機(jī)專家。但是，用戶需要能夠詳細(xì)說(shuō)明他們的信息要求；對(duì)計(jì)算機(jī)的一些理解、信息的本質(zhì)，和對(duì)各種各樣管理功能的利用將幫助用戶完成任務(wù)。</p><p>

19、　　管理信息系統(tǒng)代表性地為集成組織信息處理提供依據(jù)。信息系統(tǒng)內(nèi)部各自的應(yīng)用則由不同批次的用戶開發(fā)。如果沒(méi)有集成的處理和機(jī)制，各自的應(yīng)用也許無(wú)法協(xié)調(diào)一致和相容。在使用相同的數(shù)據(jù)時(shí)，數(shù)據(jù)項(xiàng)也許不同的被指定和不能兼容的橫跨。當(dāng)實(shí)際上一個(gè)單獨(dú)的應(yīng)用可以提供超過(guò)一個(gè)的更多的服務(wù)時(shí)，也許是分別的應(yīng)用重復(fù)的發(fā)展了。用戶想要通過(guò)使用從兩種不同的應(yīng)用中得到的數(shù)據(jù)來(lái)完成分析，也許會(huì)發(fā)現(xiàn)任務(wù)非常困難，有時(shí)甚至不可能。</p><p>

20、　　信息系統(tǒng)應(yīng)用集成的第一步是一個(gè)整體信息系統(tǒng)計(jì)劃。即使應(yīng)用系統(tǒng)是一次一個(gè)的被執(zhí)行，他們的設(shè)計(jì)可以由整體計(jì)劃指導(dǎo)，確定他們?cè)趺捶掀渌墓ぷ鳌Ｆ鋵?shí)，信息系統(tǒng)被設(shè)計(jì)成為小型系統(tǒng)的一個(gè)飛行聯(lián)盟。</p><p>　　信息系統(tǒng)集成也通過(guò)標(biāo)準(zhǔn)，指南，和程序達(dá)到，被留作管理信息系統(tǒng)的功能之用。這種標(biāo)準(zhǔn)和程序的執(zhí)行允許不同的應(yīng)用分享數(shù)據(jù)，應(yīng)付審核和控制條件，和被廣泛用戶共享。例如，一項(xiàng)應(yīng)用也許被開發(fā)來(lái)操作特殊的小型計(jì)算機(jī)。集

21、成的標(biāo)準(zhǔn)可能規(guī)定設(shè)備的選擇與中央數(shù)據(jù)庫(kù)一致。信息系統(tǒng)設(shè)計(jì)的這個(gè)趨勢(shì)有利于將應(yīng)用程序與用來(lái)支持它的數(shù)據(jù)分離。分開的數(shù)據(jù)庫(kù)是一種機(jī)制，這種機(jī)制的數(shù)據(jù)項(xiàng)是通過(guò)橫跨許多應(yīng)用來(lái)集成和對(duì)不同的用戶都可以始終一致的可利用。管理信息系統(tǒng)對(duì)于一個(gè)數(shù)據(jù)庫(kù)的需要將在下面被談?wù)摗?lt;/p><p>　　術(shù)語(yǔ)“信息”和“數(shù)據(jù)”經(jīng)?；Q的被使用。然而，信息一般被定義為對(duì)接受者有意義或者有用的數(shù)據(jù)。因此數(shù)據(jù)項(xiàng)目是生產(chǎn)出信息的原料。</p&

22、gt;<p>　　數(shù)據(jù)庫(kù)的潛在概念是，為了在處理中可以利用和具有恰當(dāng)?shù)奶匦?，?shù)據(jù)需要被管理。數(shù)據(jù)的管理包括軟件和組織。創(chuàng)造軟件和管理數(shù)據(jù)庫(kù)就是數(shù)據(jù)庫(kù)管理系統(tǒng)。當(dāng)使用數(shù)據(jù)庫(kù)的所有途徑都是通過(guò)數(shù)據(jù)庫(kù)管理系統(tǒng)被控制，所有應(yīng)用都利用一個(gè)特殊數(shù)據(jù)項(xiàng)來(lái)存取被存放在唯一一個(gè)地方的相同的數(shù)據(jù)項(xiàng)。數(shù)據(jù)項(xiàng)的一個(gè)單獨(dú)的更新，在所有方面都得到更新。用過(guò)數(shù)據(jù)庫(kù)管理系統(tǒng)的集成要求數(shù)據(jù)庫(kù)的一個(gè)中央集權(quán)。數(shù)據(jù)可能被放在一個(gè)中央計(jì)算機(jī)里或者被分散在幾個(gè)計(jì)算

23、機(jī)之中；最重要的要求是擁有一個(gè)組織功能來(lái)執(zhí)行控制。</p><p>　　對(duì)接受人來(lái)說(shuō)只接收原始數(shù)據(jù)或者甚至是總結(jié)的數(shù)據(jù)都是不夠的。數(shù)據(jù)通常需要被處理和被呈現(xiàn)出來(lái)，以結(jié)果指向所作的決定的方式。這樣，數(shù)據(jù)項(xiàng)的處理建立于決策模型。例如，一項(xiàng)投資決定相對(duì)于新的資本支出也許根據(jù)一項(xiàng)政府支出決定模型被處理。</p><p>　　決定模型可以在決策過(guò)程中被用來(lái)支持不同的階段。“智能”模型可以用來(lái)尋找問(wèn)題

24、或者機(jī)會(huì)。模型可以被用來(lái)辨認(rèn)和分析可能的解決方案。挑選模型，例如最優(yōu)化模型可以被用來(lái)發(fā)現(xiàn)最想要的解決方案。</p><p>　　換句話說(shuō)，面對(duì)各種各樣的決策情況需要多種的方法。下面是一些例子和可能被包含在一個(gè)管理信息系統(tǒng)中用來(lái)幫助分析和支持決策的模型的類型；一個(gè)全面的信息系統(tǒng)，決策者擁有一套有用的普通模型，可以應(yīng)用于許多分析和決定的情況，還有一套非常特殊的模型應(yīng)用于特別的決定。相似的模型可以用來(lái)計(jì)劃和控制。選擇的

25、模型是管理信息系統(tǒng)的模型基礎(chǔ)。</p><p>　　在不同的情況下，當(dāng)管理人員可以使用交互式的對(duì)話建立一個(gè)計(jì)劃或者通過(guò)幾個(gè)決定選擇重復(fù)敘述，模型一般是最有效的。</p><p>　　DATABASE MANAGEMENT SYSTEMS（DBMS）AND MANAGEMENT INFORMATION SYSTEM（MIS）</p><p>　　You know th

26、at a database is a collection of logically related data elements that may be structured in various ways to meet the multiple processing and retrieval needs of organizations and individuals．There’ s nothing new about data

27、bases—early ones[1] were chiseled in stone，penned on scrolls，and written on index cards．But now databases are commonly recorded on magnetizable media，and computer programs are required to perform the necessary storage an

28、d retrieval operations．</p><p>　　You’ll see in the following pages that complex data relationships and linkages may be found in all but the simplest databases[2]．The system software package that handles the

29、difficult tasks associated with creating，accessing，and maintaining database records is called a database management system（DBMS）．The programs in a DBMS package establish an interface between the database itself and the u

30、sers of the database．（These users may be applications programmers，managers and others with information nee</p><p>　　A DBMS can organize，process，and present selected data elements from the database．This capab

31、ility enables decision makers to search，probe，and query database contents in order to extract answers to nonrecurring and unplanned questions that aren’t available in regular reports[3]．These questions might initially be

32、 vague and / or poorly defined，but people can“browse”through the database until they have the needed information．In short，the DBMS will“manage”the stored data items and assemble the needed </p><p>　　If the D

33、BMS provides a way to interactively and update the database, as well as interrogate it capability allows for managing personal data-Aces however, it does not automatically leave an audit trail of actions and does not pro

34、vide the kinds of controla necessary in a multiuser organization. These-controls are only available when a set of application programs are customized for each data entry and updating function.    　　Softwa

35、re for personal computers which perform me of the DBMS functions ha</p><p>　　This is one of the most common misconceptionsabout database management systems that are used inpersonal computers．Thoroughly compr

36、ehensive andsophisticated business systems can be developed indBASh, Paradox and other DBMSs．However, theyare created by experienced programmers using theDBMS's own programming language. That is not the same as users

37、 who create and manage personal filesthat are not part of the mainstream company system．</p><p>　　Transaction Management of Database   </p><p>　　The objective of long-duration tra

38、nsactions is to model long-duration, interactive Database access sessions in application environments．The fundamental assumption about short-duration of transactions that underlies the traditional model of transactions i

39、s inappropriate for long-duration transactions．The implementation of the traditional model of transactions may cause intolerably long waits when transactions aleph to acquire locks before accessing data, and may also cau

40、se a large amount of work </p><p>　　Version System Management of Database    </p><p>　　Despite a large number of proposals on version support in the context of computer aided desi

41、gn and software engineering, the absence of a consensus on version semantics has been a key impediment to version support in database systems．Because of the differences between files and databases, it is intuitively clea

42、r that the model of versions in database systems cannot be as simple as that adopted in file systems to support software engineering．For data-bases, it may be necessary to manage not only </p><p>　　There is

43、no consensus of the definition of the term "management information system". Some writers prefer alternative terminology such as "information processing system", "information and decision system&q

44、uot;, "organizational information system", or simply "information system" to refer to the computer-based information processing system which supports the operations, management, and decision-making fu

45、nctions of an organization. This text uses “MIS” because it is descriptive and generally understood; </p><p>　　2、A definition of a management information system, as the term is generally understood, is an in

46、tegrated, user-machine system for providing information to support operations, management, and decision-making functions in an organization. The system utilizes computer hardware and software; manual procedures; models f

47、or analysis planning, control and decision making; and a database. The fact that it is an integrated system does not mean that it is a single, monolithic structure; rather, it means th</p><p>　　Computer-base

48、d user-machine system</p><p>　　3、Conceptually, a management information can exist without computer, but it is the power of the computer which makes MIS feasible. The question is not whether computers should

49、be used in management information system, but the extent to which information use should be computerized. The concept of a user-machine system implies that some tasks are best performed by humans, while others are best d

50、one by machine. The user of an MIS is any person responsible for entering input data, instructing the sy</p><p>　　4、User-machine interaction is facilitated by operation in which the user’s input-output devic

51、e( usually a visual display terminal) is connected to the computer. The computer can be a personal computer serving only one user or a large computer that serves a number of users through terminals connected by communica

52、tion lines. The user input-output device permits direct input of data and immediate output of results. For instance, a person using the computer interactively in financial planning poses </p><p>　　5、The comp

53、uter-based user-machine characteristics of an MIS affect the knowledge requirements of both system developer and system user. “computer-based” means that the designer of a management information system must have a knowle

54、dge of computers and of their use in processing. The “user-machine” concept means the system designer should also understand the capabilities of humans as system components (as information processors) and the behavior of

55、 humans as users of information.</p><p>　　6、Information system applications should not require users to be computer experts. However, users need to be able to specify their information requirements; some und

56、erstanding of computers, the nature of information, and its use in various management function aids users in this task.</p><p>　　Integrated system</p><p><b>　　集成系統(tǒng)</b></p><

57、;p>　　7、Management information system typically provide the basis for integration of organizational information processing. Individual applications within information systems are developed for and by diverse sets of us

58、ers. If there are no integrating processes and mechanisms, the individual applications may be inconsistent and incompatible. Data item may be specified differently and may not be compatible across applications that use t

59、he same data. There may be redundant development of separate applica</p><p>　　8、The first step in integration of information system applications is an overall information system plan. Even though application

60、 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 smal

61、l systems.</p><p>　　9、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 ap

62、plications 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 computer. Standards for integration may dictate t

63、hat the equipment selected be compatible with the centralized database. The trend in informat</p><p>　　Need for a database </p><p><b>　　對(duì)數(shù)據(jù)庫(kù)的需要</b></p><p>　　10、 The term

64、 “information” and “data” are frequently used interchangeably; However, information is generally defined as data that is meaningful or useful to the recipient. Data items are therefore the raw material for producing info

65、rmation.</p><p>　　11、The underlying concept of a database is that data needs to be managed in order to be available for processing and have appropriate quality. This data management includes both software an

66、d organization. The software to create and manage a database is a database management system.</p><p>　　12、When all access to any use of database is controlled through a database management system, all applic

67、ations utilizing a particular data item access the same data item which is stored in only one place. A single updating of the data item updates it for all uses. Integration through a database management system requires a

68、 central authority for the database. The data can be stored in one central computer or dispersed among several computers; the overriding requirement is that there be an organiz</p><p>　　Utilization of Models

69、 </p><p><b>　　模型的運(yùn)用</b></p><p>　　13、It is usually insufficient for human recipients to receive only raw data or even summarized data. Data usually needs to be processed and presente

70、d in such a way that the result is directed toward the decision to be made. To do this, processing of data items is based on a decision model. For example, an investment decision relative to new capital expenditures migh

71、t be processed in terms of a capital expenditure decision model. </p><p>　　14、Decision models can be used to support different stages in the decision-making process. “Intelligence” models can be used to sear

72、ch for problems and/or opportunities. Models can be used to identify and analyze possible solutions. Choice models such as optimization models maybe used to find the most desirable solution.</p><p>　　15、In o

73、ther words, multiple approaches are needed to meet a variety of decision situations. The following are examples and the type of model that might be included in an MIS to aid in analysis in support of decision-making; in

74、a comprehensive information system, the decision maker has available a set of general models that can be applied to many analysis and decision situations plus a set of very specific models for unique decisions. Similar m

75、odels are available for planning and control. The set</p><p>　　16、Models are generally most effective when the manager can use interactive dialog to build a plan or to iterate through several decision choice