【正文】 tions and requires only the least installation and management can achieve these applications. Data warehouse: The data warehouse is SQL Server 2020 contains for analysis and summary data analysis on online analytical processing tools. This function only in Oracle and other more expensive DBMS. SQL Server 2020 new features Fully expanded the SQL Server performance, reliability and usability. Increases the range of functions, specific as follows: In the aspect of relational database Graphics management enhancement The bination of enhanced database server SQL Server 2020 tools, and utilities 1, enterprise management, service management 3, 4, event detection query parsers 5 and 6, the input and output data work, server client to use tools, tools Inter use online documentation enterprise management Enterprise Management is based on a new called Microsoft Management Console (r) of public Management Microsoft Server Management environment, it is the SQL Server 2020 in one of the most important Management tools. Enterprise management can not only configuration system environment and management, but also because it SQL Server can cascade form to list all the SQL Server object, so all the SQL Server object of establishment and management can be acplished by it. In enterprise management can finish operation Management SQL Server Server. Establish and manage database, Establish and manage, view, storage process, triggering role, rules, procedures, by default, such as user defined object database of data types, Backup database and transaction log, Restore database, Copy database, Set task scheduling, Set alarm, Provide crossserver draganddrop controls operating, Manage the user accounts, Establish Transact SQL mands and the management and control of the SQL statement Email. In the enterprise management in the window contains two on the window directory tree right is the active window, showing the contents of the window. The window, click on various projects can deploy plus mitteeamp。 服務(wù)管理器（ Service Manager） SQL Server 服務(wù)管理器是在服務(wù)器端實際工作時最有 用的實用程序，服務(wù)管理器用來啟動、暫停、繼續(xù)和停止數(shù)據(jù)庫服務(wù)器的實時服務(wù)，其提供的服務(wù)類型包括： SQL Server、 SQL Server代理、 Microsoft搜索和分布式事務(wù)協(xié)調(diào)器等。 》單擊左側(cè)窗口中的加號，可以展開各個項目包含的子項目。 用企業(yè)管理可以完成的操作 》管理 SQL Server 服務(wù)器；建立與管理數(shù)據(jù)庫；建立與管理表、視圖、存儲過程、觸發(fā)程序、角色、規(guī)則、默認(rèn)值等數(shù)據(jù)庫對象，以及用戶定義的數(shù)據(jù)類型；備份數(shù)據(jù)庫 和事務(wù)日志、 恢復(fù)數(shù)據(jù)庫；復(fù)制數(shù)據(jù)庫；設(shè)置任務(wù)調(diào)度；設(shè)置警報；提供跨服務(wù)器的拖放控制操作；管理用戶賬戶；建立 TransactSQL 命令語句以及管理和控制 SQL Mail。增加了一系列的功能，具體如下： 》在關(guān)系數(shù)據(jù)庫方面的增強(qiáng) 》圖形管理增強(qiáng) 》增強(qiáng)的聯(lián)合數(shù)據(jù)庫服務(wù)器 SQL Server 2020 工具和實用程序 企業(yè)管理器 服務(wù)管理器 查詢分析器 事件探查器 導(dǎo)入和導(dǎo)出數(shù)據(jù) 服務(wù)器網(wǎng)絡(luò)使用工具 客戶端網(wǎng)絡(luò)使用工具 聯(lián)機(jī)幫助文檔 企業(yè)管理器 企業(yè)管理器是基于一種新的被稱為微軟管理控制臺（ Microsoft Management Console)的公共服務(wù)器管理環(huán)境，它是 SQL Server 2020 中最重要的一個管理工具。這個功能只在 Oracle和其他更昂 貴的 DBMS 中才有。開發(fā)人員可以更加快速地交付 SQL Server 應(yīng)用程序，而且只需要進(jìn)行最少的安裝和管理就可以實現(xiàn)這些應(yīng)用程序。 》企業(yè)級數(shù)據(jù)庫功能： SQL Server 2020 分布式查詢可以引用來自不同數(shù)據(jù)庫的數(shù)據(jù)，而且這些對于用戶來說是完全透明的；分布式數(shù)據(jù)庫將保證任何分布式數(shù)據(jù)更新時的完整性；復(fù)制可以使我們能夠維護(hù)多個數(shù)據(jù)復(fù)本，這些用戶能夠自主地進(jìn)行工作，然后再將所做的修改合并到發(fā)布數(shù)據(jù)庫； SQL Server 2020關(guān)系數(shù)據(jù)庫引擎能夠充分保護(hù)數(shù)據(jù)完整性，還可以將管理并發(fā)修改數(shù)據(jù)庫開銷到最小。 》可伸縮性與可用性： 可跨越從運行 Windows 95/98 的膝上型電腦到運行 Windows 2020 的大型多處理器等多種平臺使用。雖然開發(fā)版的功能齊備，但是只被授權(quán)為一個開發(fā)和測試系統(tǒng)，而不是一個產(chǎn)品服務(wù)器。 》開發(fā)者版（ Developer Edition） 適用于應(yīng)用程序開發(fā)的版本，支 持除圖形化語言設(shè)置以外的 SQL Server2020的所有其它功能。 》個人版（ Personal Edition） 主要適用于移動用戶，因為他們經(jīng)常從網(wǎng)絡(luò)上斷開，而運行的應(yīng)用程序卻仍然需要 SQL Server 2020 的支持。但是，不具有支持大型數(shù)據(jù)庫，數(shù)據(jù)倉庫和網(wǎng)站的功能。 》標(biāo)準(zhǔn)版（ Standard Edition） 實用范圍是小型的工作組或部門。 關(guān)系數(shù)據(jù)庫（ RDBMS)管理系統(tǒng)功能： 》維護(hù)數(shù)據(jù)庫數(shù)據(jù)之間的關(guān)系； 》保證數(shù)據(jù)存儲的正確性； 》當(dāng)出現(xiàn)系統(tǒng)故障的時候，將所有數(shù)據(jù)恢復(fù)到能夠保證一致行的某種狀態(tài) RDBMS:SQL Server， Oracle， DB/2,Sybase， Informix NonRDBMS(Filebased）： Foxpro， Access 二、 SQL Server 2020 的版本 SQL Server 2020 常見版本有： 》企業(yè)版（ Enterprise Edition） 支持所有 SQL Server 2020 的功能。 3. If the JSP in the package good Cookie object to send to the client, the use of the response addCookie () method. Format: (c) 4. Save to read the client39。s puter to store information on and then get back to it. For example, a Web site may be generated for each visitor a unique ID, and then to Cookie in the form of documents stored in each user39。s first visit to a server on the JSP pages, JSP engines produce a session object, and assigned a String type of ID number, JSP engine at the same time, the ID number sent to the client, stored in Cookie, this session objects, and customers on the establishment of a onetoone relationship. When a customer to connect to the server of the other pages, customers no longer allocated to the new session object, until, close your browser, the clientserver object to cancel the session, and the conversation, and customer relationship disappeared. When a customer reopen the browser to connect to the server, the server for the customer to create a new session object. 四 . aplication target 1. What is the application: Servers have launched after the application object, when a customer to visit the site between the various pages here, this application objects are the same, until the server is down. But with the session difference is that all customers of the application objects are the same, that is, all customers