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《數(shù)據(jù)庫管理》外文翻譯.doc

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《數(shù)據(jù)庫管理》外文翻譯,《數(shù)據(jù)庫管理》畢業(yè)設(shè)計(論文)外文rn_資料翻譯,附帶原文數(shù)據(jù)庫管理數(shù)據(jù)庫(有時拼成database)也稱為電子數(shù)據(jù)庫,是指由計算機(jī)特別組織的用下快速查找和檢索的任意的數(shù)據(jù)或信息集合。數(shù)據(jù)庫與其它數(shù)據(jù)處理操作協(xié)同工作,其結(jié)構(gòu)要有助于數(shù)據(jù)的存儲、檢索、修改和刪除。數(shù)據(jù)庫可存儲在磁盤或磁帶、光盤或某些輔助存儲設(shè)備上。一個數(shù)...
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《數(shù)據(jù)庫管理》畢業(yè)設(shè)計(論文)外文rn_資料翻譯,附帶原文

數(shù)據(jù)庫管理
數(shù)據(jù)庫(有時拼成Database)也稱為電子數(shù)據(jù)庫,是指由計算機(jī)特別組織的用下快速查找和檢索的任意的數(shù)據(jù)或信息集合。數(shù)據(jù)庫與其它數(shù)據(jù)處理操作協(xié)同工作,其結(jié)構(gòu)要有助于數(shù)據(jù)的存儲、檢索、修改和刪除。數(shù)據(jù)庫可存儲在磁盤或磁帶、光盤或某些輔助存儲設(shè)備上。
一個數(shù)據(jù)庫由一個文件或文件集合組成。這些文件中的信息可分解成一個個記錄,每個記錄有一個或多個域。域是數(shù)據(jù)庫存儲的基本單位,每個域一般含有由數(shù)據(jù)庫描述的屬于實(shí)體的一個方面或一個特性的信息。用戶使用鍵盤和各種排序命令,能夠快速查找、重排、分組并在查找的許多記錄中選擇相應(yīng)的域,建立特定集上的報表。
數(shù)據(jù)庫記錄和文件的組織必須確保能對信息進(jìn)行檢索。早期的系統(tǒng)是順序組織的(如:字母順序、數(shù)字順序或時間順序);直接訪問存儲設(shè)備的研制成功使得通過索引隨機(jī)訪問數(shù)據(jù)成為可能。用戶檢索數(shù)據(jù)庫信息的主要方法是query(查詢)。通常情況下,用戶提供一個字符串,計算機(jī)在數(shù)據(jù)庫中尋找相應(yīng)的字符序列,并且給出字符串在何處出現(xiàn)。比如,用戶必須能在任意給定時間快速處理內(nèi)部數(shù)據(jù)。而且,大型企業(yè)和其它組織傾向于建立許多獨(dú)立的文件,其中包含相互關(guān)聯(lián)的甚至重疊的數(shù)據(jù),這些數(shù)據(jù)、處理活動經(jīng)常需要和其它文件的數(shù)據(jù)相連。為滿足這些要求,開發(fā)郵各種不同類型的數(shù)據(jù)庫管理系統(tǒng),如:非結(jié)構(gòu)化的數(shù)據(jù)庫、層次型數(shù)據(jù)庫、網(wǎng)絡(luò)型數(shù)據(jù)庫、關(guān)系型數(shù)據(jù)庫、面向?qū)ο笮蛿?shù)據(jù)庫。

Database Management
Database (sometimes spelled database) is also called an electronic database, referring to any collections of data, or information, that is specially organized for rapid search and retrieva l by a computer. Databases are structured to facilitate the storage, retrieva l modification and deletion of data in conjunction with various data-processing operations. Database can be stored on magnetic disk or tape, optical disk, or some other secondary storage device.
A database consists of a file or a set of files. The information in the these files may be broken down into records, each of which consists of one or more fields are the basic units of data storage, and each field typically contains information pertaining to one aspect or attribute of the entity described by the database. Using keywords and various sorting commands, users can rapidly search, rearrange, group, and select the fields in many records to retrieve or create reports on particular aggregates of data.
Database records and files must be organized to allow retrieva l of the information. Early system were arranged sequentially (i.e., alphabetically, numerically, or chronologically); the development of direct-access storage devices made possible random access to data via indexes. Queries are the main way users retrieve database information. Typically the user provides a string of characters, and the computer searches the database for a corresponding sequence and provides the source materials in which those characters appear. A user can request, for example, all records in which the content of the field for a person’s last name is the word Smith.