數(shù)據(jù)庫管理 畢業(yè)論文外文資料翻譯

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1、 畢業(yè)設(shè)計(論文) 外文資料翻譯 學(xué)生姓名： 學(xué) 號： 所在學(xué)院： 電子與信息工程學(xué)院 專 業(yè)： 計算機(jī)科學(xué)與技術(shù) 指導(dǎo)教師： 2011年 12月 25 日 English Data Original Text Translates the foreign materials: ① Author: Feras T.Dabous ② Book title (or

2、paper topic): Database Management ③ Publishing house (or publication name): http:// ④ Publication time (or registration number): july 2004 Database Management Database (sometimes spelled database) is also called an electronic database, referring to any collections of data, or information, that

3、 is specially organized for rapid search and retrieval by a computer. Databases are structured to facilitate the storage, retrieval 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 s

4、econdary 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 a

5、ttribute 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 retr

6、ieval 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 use

7、r 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. The m

8、any users of a large database must be able to manipulate the information within it quickly at any given time. Moreover, large business and other organizations tend to build up many independent files containing related and even overlapping data, and their data, processing activities often require the

9、 linking of data from several files. Several different types of database management systems have been developed to support these requirements: flat, hierarchical, network, relational, and object-oriented. In flat databases, records are organized according to a simple list of entities; many simple

10、databases for personal computers are flat in structure. The records in hierarchical databases are organized in a treelike structure, with each level of records branching off into a set of smaller categories. Unlike hierarchical databases, which provide single links between sets of records at differe

11、nt levels, network databases create multiple linkages between sets by placing links, or pointers, to one set of records in another; the speed and versatility of network databases have led to their wide use in business. Relational databases are used where associations among files or records cannot be

12、 expressed by links; a simple flat list becomes one table, or “relation”, and multiple relations can be mathematically associated to yield desired information. Object-oriented databases store and manipulate more complex data structures, called “objects”, which are organized into hierarchical classes

13、 that may inherit properties from classes higher in the chain; this database structure is the most flexible and adaptable. The information in many databases consists of natural-language texts of documents; number-oriented database primarily contain information such as statistics, tables, financial

14、data, and raw scientific and technical data. Small databases can be maintained on personal-computer systems and may be used by individuals at home. These and larger databases have become increasingly important in business life. Typical commercial applications include airline reservations, production

15、 management, medical records in hospitals, and legal records of insurance companies. The largest databases are usually maintained by governmental agencies, business organizations, and universities. These databases may contain texts of such materials as catalogs of various kinds. Reference databases

16、contain bibliographies or indexes that serve as guides to the location of information in books, periodicals, and other published literature. Thousands of these publicly accessible databases now exist, covering topics ranging from law, medicine, and engineering to news and current events, games, clas

17、sified advertisements, and instructional courses. Professionals such as scientists, doctors, lawyers, financial analysts, stockbrokers, and researchers of all types increasingly rely on these databases for quick, selective access to large volumes of information. 1．DBMS Structuring Techniques Seque

18、ntial, direct, and other file processing approaches are used to organize and structure data in single files. But a DBMS is able to integrate data elements from several files to answer specific user inquiries for information. That is, the DBMS is able to structure and tie together the logically relat

19、ed data from several large files. Logical Structures. Identifying these logical relationships is a job of the data administrator. The DBMS may then employ one of the following logical structuring techniques during storage access, and retrieval operations. List structures. In this logical approach

20、, records are linked together by the use of pointers. A pointer is a data item in one record that identifies the storage location of another logically related record. Records in a customer master file, for example, will contain the name and address of each customer, and each record in this file is i

21、dentified by an account number. During an accounting period, a customer may buy a number of items on different days. Thus, the company may maintain an invoice file to reflect these transactions. A list structure could be used in this situation to show the unpaid invoices at any given time. Each reco

22、rd in the customer in the invoice file. This invoice record, in turn, would be linked to later invoices for the customer. The last invoice in the chain would be identified by the use of a special character as a pointer. Hierarchical (tree) structures. In this logical approach, data units are struct

23、ured in multiple levels that graphically resemble an “upside down” tree with the root at the top and the branches formed below. There’s a superior-subordinate relationship in a hierarchical (tree) structure. Below the single-root data component are subordinate elements or nodes, each of which, in tu

24、rn, “own” one or more other elements (or none). Each element or branch in this structure below the root has only a single owner. Thus, a customer owns an invoice, and the invoice has subordinate items. The branches in a tree structure are not connected. Network Structures. Unlike the tree approach,

25、 which does not permit the connection of branches, the network structure permits the connection of the nodes in a multidirectional manner. Thus, each node may have several owners and may, in turn, own any number of other data units. Data management software permits the extraction of the needed infor

26、mation from such a structure by beginning with any record in a file. Relational structures. A relational structure is made up of many tables. The data are stored in the form of “relations” in these tables. For example, relation tables could be established to link a college course with the instructo

27、r of the course, and with the location of the class. To find the name of the instructor and the location of the English class, the course/instructor relation is searched to get the name (“Fitt”), and the course/location relation is a relatively new database structuring approach that’s expected to b

28、e widely implemented in the future. Physical Structures. People visualize or structure data in logical ways for their own purposes. Thus, records R1 and R2 may always be logically linked and processed in sequence in one particular application. However, in a computer system it’s quite possible that

29、these records that are logically contiguous in one application are not physically stored together. Rather, the physical structure of the records in media and hardware may depend not only on the I/O and storage devices and techniques used, but also on the different logical relationships that users ma

30、y assign to the data found in R1and R2. For example, R1 and R2 may be records of credit customers who have shipments send to the same block in the same city every 2 weeks. From the shipping department manager’s perspective, then, R1 and R2 are sequential entries on a geographically organized shippin

31、g report. But in the A/R application, the customers represented by R1 and R2 may be identified, and their accounts may be processed, according to their account numbers which are widely separated. In short, then, the physical location of the stored records in many computer-based information systems i

32、s invisible to users. 2．Database Management Features of Oracle Oracle includes many features that make the database easier to manage. We’ve divided the discussion in this section into three categories: Oracle Enterprise Manager, add-on packs, backup and recovery. 2.1 Oracle Enterprise Manager

33、As part of every Database Server, Oracle provides the Oracle Enterprise Manager (EM), a database management tool framework with a graphical interface used to manage database users, instances, and features (such as replication) that can provide additional information about the Oracle environment. Pr

34、ior to the Oracle8i database, the EM software had to be installed on Windows 95/98 or NT-based systems and each repository could be accessed by only a single database manager at a time. Now you can use EM from a browser or load it onto Windows 95/98/2000 or NT-based systems. Multiple database admini

35、strators can access the EM repository at the same time. In the EM repository for Oracle9i, the super administrator can define services that should be displayed on other administrators’ consoles, and management regions can be set up. 2.2 Add-on packs Several optional add-on packs are available for

36、Oracle, as described in the following sections. In addition to these database-management packs, management packs are available for Oracle Applications and for SAP R/3. (1) standard Management Pack The Standard Management Pack for Oracle provides tools for the management of small Oracle databases

37、(e.g., Oracle Server/Standard Edition). Features include support for performance monitoring of database contention, I/O, load, memory use and instance metrics, session analysis, index tuning, and change investigation and tracking. (2) Diagnostics Pack You can use the Diagnostic Pack to monitor,

38、 diagnose, and maintain the health of Enterprise Edition databases, operating systems, and applications. With both historical and real-time analysis, you can automatically avoid problems before they occur. The pack also provides capacity planning features that help you plan and track future system-r

39、esource requirements. (3) Tuning Pack With the Tuning Pack, you can optimise system performance by identifying and tuning Enterprise Edition databases and application bottlenecks such as inefficient SQL, poor data design, and the improper use of system resources. The pack can proactively discover

40、 tuning opportunities and automatically generate the analysis and required changes to tune the systems. (4) Change Management Pack The Change Management Pack helps eliminate errors and loss of data when upgrading Enterprise Edition databases to support new applications. It impact and complex depe

41、ndencies associated with application changes and automatically perform database upgrades. Users can initiate changes with easy-to-use wizards that teach the systematic steps necessary to upgrade. (5) Availability Oracle Enterprise Manager can be used for managing Oracle Standard Edition and/or Ent

42、erprise Edition. Additional functionality is provided by separate Diagnostics, Tuning, and Change Management Packs. 2.3 Backup and Recovery As every database administrator knows, backing up a database is a rather mundane but necessary task. An improper backup makes recovery difficult, if not impos

43、sible. Unfortunately, people often realize the extreme importance of this everyday task only when it is too late –usually after losing business-critical data due to a failure of a related system. The following sections describe some products and techniques for performing database backup operations.

44、 (1) Recovery Manager Typical backups include complete database backups (the most common type), database backups, control file backups, and recovery of the database. Previously, Oracle’s Enterprise Backup Utility (EBU) provided a similar solution on some platforms. However, RMAN, with its Recovery

45、 Catalog stored in an Oracle database, provides a much more complete solution. RMAN can automatically locate, back up, restore, and recover databases, control files, and archived redo logs. RMAN for Oracle9i can restart backups and restores and implement recovery window policies when backups expire.

46、 The Oracle Enterprise Manager Backup Manager provides a GUI-based interface to RMAN. (2) Incremental backup and recovery RMAN can perform incremental backups of Enterprise Edition databases. Incremental backups back up only the blocks modified since the last backup of a datafile, tablespace, or d

47、atabase; thus, they’re smaller and faster than complete backups. RMAN can also perform point-in-time recovery, which allows the recovery of data until just prior to a undesirable event. (3) Legato Storage Manager Various media-management software vendors support RMAN. Oracle bundles Legato Storage

48、 Manager with Oracle to provide media-management services, including the tracking of tape volumes, for up to four devices. RMAN interfaces automatically with the media-management software to request the mounting of tapes as needed for backup and recovery operations. (4) Availability While basic re

49、covery facilities are available for both Oracle Standard Edition and Enterprise Edition, incremental backups have typically been limited to Enterprise Edition. 外文資料中文譯文 所譯外文資料： ① 作者：Feras T.Dabous ② 書名（或論文題目）：數(shù)據(jù)庫管理 ③ 出版社（或刊物名稱）：http:// ④ 出版時間（或刊號）：july 2004 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，

50、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）

51、；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。 在非結(jié)構(gòu)化的數(shù)據(jù)庫中，按照實體的一個簡單列表組織記錄；很多個人計算機(jī)的簡易數(shù)

52、據(jù)庫是非結(jié)構(gòu)的。層次型數(shù)據(jù)庫按樹型組織記錄，每一層的記錄分解成更小的屬性集。層次型數(shù)據(jù)庫在不同層的記錄集之間提供一個單一鏈接。與此不同，網(wǎng)絡(luò)型數(shù)據(jù)庫在不同記錄集之間提供多個鏈接，這是通過設(shè)置指向其它記錄集的鏈或指針來實現(xiàn)的。網(wǎng)絡(luò)型數(shù)據(jù)庫的速度及多樣性使其在企業(yè)中得到廣泛應(yīng)用。當(dāng)文件或記錄間的關(guān)系不能用鏈表達(dá)時，使用關(guān)系型數(shù)據(jù)庫。一個表或一個“關(guān)系”，就是一個簡單的非結(jié)構(gòu)列表。多個關(guān)系可通過數(shù)學(xué)關(guān)系提供所需信息。面向?qū)ο蟮臄?shù)據(jù)庫存儲并處理更復(fù)雜的稱為對象的數(shù)據(jù)結(jié)構(gòu)，可組織成有層次的類，其中的每個類可以繼承層次鏈中更高一級類的特性，這種數(shù)據(jù)庫結(jié)構(gòu)最靈活，最具適應(yīng)性。 很多數(shù)據(jù)庫包含自然語言文本信

53、息，可由個人在家中使用。小型及稍大的數(shù)據(jù)庫在商業(yè)領(lǐng)域中占有越來越重要的地位。典型的商業(yè)應(yīng)用包括航班預(yù)訂、產(chǎn)品管理、醫(yī)院的醫(yī)療記錄以及保險公司的合法記錄。最大型的數(shù)據(jù)庫通常用天政府部門、企業(yè)、大專院校等。這些數(shù)據(jù)庫存有諸如摘要、報表、成文的法規(guī)、通訊錄、報紙、雜志、百科全書、各式目錄等資料。索引數(shù)據(jù)庫包含參考書目或用于找到相關(guān)書籍、期刊及其它參考文獻(xiàn)的索引。目前有上萬種可公開訪問的數(shù)據(jù)庫，內(nèi)容包羅萬象，從法律、醫(yī)學(xué)、工程到新聞、時事、游戲、分類廣告、指南等?？茖W(xué)家、醫(yī)生、律師、財經(jīng)分析師、股票經(jīng)紀(jì)人等專家和各類研究者越來越多地依賴這些數(shù)據(jù)庫從大量的信息中做快速的查找訪問。 1．?dāng)?shù)據(jù)庫管理系統(tǒng)的

54、組織技術(shù) 順序的、直接的以及其他的文件處理方式常用于單個文件中數(shù)據(jù)的組織和構(gòu)造，而DBMS可綜合幾個文件的數(shù)據(jù)項以回答用戶對信息的查詢，這就意味著DBMS能夠訪問和檢索非關(guān)鍵記錄字段的數(shù)據(jù)，即DBMS能夠?qū)讉€大文件夾中邏輯相關(guān)的數(shù)據(jù)組織并連接在一起。 邏輯結(jié)構(gòu)：確定這些邏輯關(guān)系是數(shù)據(jù)管理者的任務(wù)，由數(shù)據(jù)定義語言完成。DBMS在存儲、訪問和檢索操作過程中可選用以下邏輯構(gòu)造技術(shù)： 鏈表結(jié)構(gòu)：在該邏輯方式中，記錄通過指針鏈接在一起。指針是記錄本中的一相數(shù)據(jù)項，它指出另一個邏輯相關(guān)的記錄的存儲位置，例如，顧客主文件中的記錄將包含每個顧客的姓名和地址，而且該文件中的每個記錄都由一個賬號標(biāo)識。在記

55、賬期間，顧客可在不同時間購買許多東西。公司保存一個發(fā)票文件以反映這下地交易，這種情況下可使用鏈表結(jié)構(gòu)，以顯示給定時間內(nèi)未支付的發(fā)票。顧客文件中的每個記錄都包含這樣一個字段，該字段指向發(fā)票文件中該顧客的第一個發(fā)票的記錄位置，該發(fā)票記錄又依次與該顧客的下一個發(fā)票記錄相連，此鏈接的最后一個發(fā)票記錄由一個作為指針的特殊字符標(biāo)識。 層次（樹型）結(jié)構(gòu)：該邏輯方式中，數(shù)據(jù)單元的多級結(jié)構(gòu)類似一棵“倒立”的樹，該樹的樹根在頂部，而樹枝向下延伸。在層次（樹型）結(jié)構(gòu)中存在主-從關(guān)系，惟一的根數(shù)據(jù)下是從屬的元或節(jié)點(diǎn)，而每個元或樹枝都只有一個所有者，在樹型結(jié)構(gòu)中，樹枝不能相連。 網(wǎng)狀結(jié)構(gòu)：網(wǎng)狀結(jié)構(gòu)不像樹型結(jié)構(gòu)那樣不

56、允許樹枝相連，它允許節(jié)點(diǎn)間多個方向連接，這樣，每個節(jié)點(diǎn)都可能有幾個所有者，中央電視臺它又可能擁有任意多個其他數(shù)據(jù)單元。數(shù)據(jù)管理軟件允許從文件的任一記錄開始提取該結(jié)構(gòu)中的所需信息。 關(guān)系型結(jié)構(gòu)：關(guān)系型結(jié)構(gòu)由許多表格組成，數(shù)據(jù)則以“關(guān)系”的形式存儲在這些表中。例如，可建立一些關(guān)系表，將大學(xué)課程同任課教師及上課地點(diǎn)連接起來。為了找到英語課的上課地點(diǎn)和教師名，首先查詢課程/教師關(guān)系表得到名字（為“Fitt”），再查詢課程/地點(diǎn)關(guān)系表得到地點(diǎn)（“Main 142”），當(dāng)然，也可能有其他關(guān)系。這是一個相當(dāng)新穎的數(shù)據(jù)庫組織技術(shù)，將來有望得到廣泛應(yīng)用。 物理結(jié)構(gòu)：人們總是為了各自的目的，按邏輯方式設(shè)想或組

57、織數(shù)據(jù)。因此，在一個具體應(yīng)用中，記錄R1和R2是邏輯相連且順序處理的，但是，在計算機(jī)系統(tǒng)中，這些在一個應(yīng)用中邏輯相鄰的記錄，物理位置完全可能不在一起。記錄在介質(zhì)和硬件中的物理結(jié)構(gòu)不僅取決于所采用的I/O設(shè)備、存儲設(shè)備及輸入輸出和存取技術(shù)，而且還取決于用戶定義的R1和R2中數(shù)據(jù)的邏輯關(guān)系。例如，R1和R2可能是持有信用卡的顧客記錄，而顧客要求每兩周將貨物運(yùn)送到同一個城市的同一個街區(qū)，而從運(yùn)輸部門的管理者看，R1和R2是按地理位置組織的運(yùn)輸記錄的順序項，但是在A/R應(yīng)用中，可找到R1長表示的顧客，并且可根據(jù)其完全不同的賬號處理他們的賬目。簡言之，在許多計算機(jī)化的信息記錄中，存儲記錄的物理位置用戶是

58、看不見的。 2．Oracle的數(shù)據(jù)庫管理功能 Oracle 包括許多使數(shù)據(jù)庫易于管理的功能，分三部分討論：Oracle 企業(yè)管理器、附加包、備份和恢復(fù)。 2.1 Oracle 企業(yè)管理器 和任何數(shù)據(jù)庫服務(wù)器一樣，Oracle 數(shù)據(jù)庫服務(wù)器包括以下部分：Oracle 企業(yè)管理器（IM）、一個帶有圖形接口的用于管理數(shù)據(jù)庫用戶、實例和提供Oracle 環(huán)境等附加信息功能（如：復(fù)制）的數(shù)據(jù)庫管理工具框架。 在Oracle8i數(shù)據(jù)庫之前，EM 軟件必須安裝在Windows95/98或者基于NT 的系統(tǒng)中，而且每個庫每次只能由一個數(shù)據(jù)庫管理者訪問。如今你可以通過瀏覽器或者把EM 裝入Window

59、95/98/2000 或基于NT 的系統(tǒng)中來使用EM。多個數(shù)據(jù)庫管理員可以同時訪問EM庫。在Oracle9i的EM版中，超級管理員可以定義在普通管理員的控制臺上顯示的服務(wù)，并能建立管理區(qū)域。 2.2 附加包 正如下面所描述的那樣，Oracle可使用一些可選的附加包，還有用于Oracle應(yīng)用程序和SAP R/3的管理包。 （1）標(biāo)準(zhǔn)管理包 Oracle的標(biāo)準(zhǔn)管理包提供了用于小型Oracle數(shù)據(jù)庫的管理工具（如：Oracle服務(wù)器/標(biāo)準(zhǔn)版）。功能包括：對數(shù)據(jù)庫爭用、輸入/輸出、裝載、內(nèi)存使用和實例、對話分析、索引調(diào)整進(jìn)行監(jiān)控，并改變調(diào)查和跟蹤。 （2）診斷包 利用診斷包，可以監(jiān)控、診斷

60、及維護(hù)企業(yè)版數(shù)據(jù)庫、操作系統(tǒng)和應(yīng)用程序的安全。用有關(guān)歷史和實時的分析，可自動的在問題發(fā)生前將其消除。診斷包還提供空間管理功能，有助于對未來系統(tǒng)資源需要的計劃和跟蹤。 （3）調(diào)整包 利用調(diào)整包，可確定并調(diào)整企業(yè)版數(shù)據(jù)庫和應(yīng)用系統(tǒng)的瓶頸，如效率低的SQL、很差的數(shù)據(jù)設(shè)計、系統(tǒng)資源的不當(dāng)使用，從而優(yōu)化系統(tǒng)性能。調(diào)整包能提前發(fā)現(xiàn)調(diào)整時機(jī)，并自動生成分析和需求變化來調(diào)整系統(tǒng)。 （4）變化管理包 變化管理包在升級企業(yè)版數(shù)據(jù)庫時幫助排錯和避免丟失數(shù)據(jù)，以達(dá)到支持新的應(yīng)用程序的目的。該包能分析與應(yīng)用程序變動有關(guān)的影響和復(fù)雜依賴關(guān)系并自動升級數(shù)據(jù)庫。用戶可使用一種簡單的向?qū)О幢匾牟襟E來升級。 （5）

61、可用性 Oracle 企業(yè)管理器可用管理Oracle標(biāo)準(zhǔn)版或企業(yè)版。在標(biāo)準(zhǔn)版中，用于診斷、調(diào)整和改變實例的附加功能由標(biāo)準(zhǔn)管理包提供。對于企業(yè)版，這些附加的功能由單獨(dú)的診斷包、調(diào)整包和變化管理包提供。 2.3備份和恢復(fù) 正如每個數(shù)據(jù)庫管理者所熟知的，對數(shù)據(jù)庫做備份是一件很普通但又必要的工作。一次不當(dāng)?shù)膫浞輹箶?shù)據(jù)庫難于恢復(fù)甚至不可恢復(fù)。不幸的是，人們往往在相關(guān)系統(tǒng)發(fā)生故障而丟失了重要的業(yè)務(wù)數(shù)據(jù)后才認(rèn)識到這項日常工作的重要。 下面介紹一些實現(xiàn)數(shù)據(jù)庫備份操作的產(chǎn)品技術(shù)。 （1）

62、恢復(fù)管理者 典型的備份包括完整的數(shù)據(jù)庫備份（最普通的類型）、桌面空間備份、數(shù)據(jù)文件備份、控件備份和存檔注冊備份。Oracle8i為數(shù)據(jù)服務(wù)器管理備份和恢復(fù)管理器（RMAN）。以前，Oracle的企業(yè)備份工具（EBU）在一些平臺上提供了相似的解決方案。然而，RMAN及其存儲在Oracle數(shù)據(jù)庫中的恢復(fù)目錄提供了更完整的解決方案。RMAN可以自動定位、備份、存儲并恢復(fù)數(shù)據(jù)文件、控制文件和存檔記錄注冊。當(dāng)備份到期時，Oracle9i的RMAN可以重新啟動備份和恢復(fù)來實現(xiàn)恢復(fù)窗口的任務(wù)。Oracle企業(yè)管理器的備份管理器曾RMAN提供基于圖形用戶界面的接口。 （2） 附加備份和恢復(fù) RMAN能夠執(zhí)行企業(yè)版數(shù)據(jù)庫的附加備份。附加備份僅備份上一次備份后改變了的數(shù)據(jù)文件、桌面空間或數(shù)據(jù)庫塊，因此，它比完整的備份占用時間短而且速度快。RMAN也能執(zhí)行及時指向的恢復(fù)，這種恢復(fù)能在一個不期望的事件發(fā)片之前（如錯誤的刪除表格）恢復(fù)數(shù)據(jù)。 （3） 連續(xù)存儲管理器 許多媒體軟件商支持RMAN。Oracle捆綁了連續(xù)存儲管理器來提供媒體管理服務(wù)，包括為至多四臺設(shè)備提供磁帶容量跟蹤的服務(wù)。RMAN界面自動地與媒體管理軟件一起來管理備份和恢復(fù)操作必須的磁帶設(shè)備。 （4） 可用性 盡管標(biāo)準(zhǔn)版和企業(yè)版的Oracle都有基本的恢復(fù)機(jī)制，但附加備份僅限于企業(yè)版。