外文翻譯---access2000關(guān)系型數(shù)據(jù)庫-數(shù)據(jù)庫(完整版)
【正文】 開發(fā)工具，用戶可以方便的設(shè)計、修改、瀏覽一條記錄數(shù)據(jù)的基本表；可以在表數(shù)據(jù)中進(jìn)行各種篩選和查詢操作；可以設(shè)計和使用各種窗體以實現(xiàn)數(shù)據(jù)顯示和操作；可以根據(jù)表數(shù)據(jù)設(shè)計打印各種報表；可以設(shè)計和使用宏，對表進(jìn)行一系列特定的操作。并且在數(shù)據(jù)需要作報表輸出的時候，又要反過來將已經(jīng)分散設(shè)置的大量的兩維數(shù)據(jù)表，再利用索引的技術(shù)進(jìn)行表的連接后，才能找到我們所需要的數(shù)據(jù)，而這又將會影響到應(yīng)用系統(tǒng)的響應(yīng)速度。 關(guān)系型數(shù)據(jù)庫管理系統(tǒng)本身固有的局限性，表現(xiàn)在以下三個方面： 關(guān)系數(shù)據(jù)庫所采用的兩維表數(shù)據(jù)模型，不能有效地處理在大多數(shù)事務(wù)處理應(yīng)用中，典型存在的多維數(shù)據(jù)。 Access2020 是一種關(guān)系型的數(shù)據(jù)庫工具，關(guān)系數(shù)據(jù)庫是已經(jīng)開發(fā)的最常用的數(shù)據(jù)庫之一。這樣一個變化給數(shù)據(jù)庫技術(shù)帶來了巨大的挑戰(zhàn)，數(shù)據(jù)庫管理的對象已經(jīng)不再局限于文本數(shù)據(jù)等一些簡單的數(shù)據(jù)類型，而是需要描述和保存大量多媒體非結(jié)構(gòu)化的復(fù)雜數(shù)據(jù)，以及數(shù)據(jù)之間的關(guān)系。它是一個功能非常強(qiáng)大的數(shù)據(jù)庫管理系統(tǒng)的 MIS 系統(tǒng)開發(fā)工具。 Data tables can design various print statements。s mandate. If a user with the same time these two powers, the right set of user security database for a visit, then He had such authority is the intersection of the two powers. The Access20202020database, the group of users’ access to the database and the authority set up work, pleted only through the administrator. Set up the authority include: Open/Run, read design, design modifications, management, read data, update data insertion and deletion of data. Relational database management system inherent limitations in the following three aspects: Relational database used in the twodimensional table data model, can not effectively handle the majority of business applications, Typical of multidimensional data. Its inevitable result is that in plex ways, the interaction of the dramatic increase in the number of tables, not very good but also to provide realistic simulation of the data model. Relational database as they use more data model, which might lead to a massive storage space and wasting a lot of increase, and cause the system to respond to the declining performance. Furthermore, the data in reality, there are many types of relational database is not well addressed. Static applications such as report generation, and the design of the relational database management system after no response and efficient business processing for the optimization process. The result is often some relational database products, in the GUI and Web Services processing, not achieved the desired results. Unless additional hardware investment, but it does not resolve the fundamental problem. Relations with the twodimensional database table data model can deal with the majority of business application of a typical multi dimensional data, but the results are often the establishment and use of a large amount of data forms, it is difficult to establish a simulation of realworld data model. And the need for data output statements when they, in turn, would have dispersed the large number of twodimensional data tables. Reuse indexing technology linking the table in order to find all the necessary data, this, in turn, is bound to affect the use of the response speed. Database v
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