【導讀】它由一些Java語言編寫的類和界面組成。JDBC為數(shù)據(jù)庫應用開發(fā)人員、數(shù)。言編寫完整的數(shù)據(jù)庫應用程序。說到JDBC，很容易讓人聯(lián)想到另一個十分熟悉的字眼“ODBC”。它們之間有沒有聯(lián)系。如果有，那么它們之間又是怎樣的關系呢？它是一種用來在相關或不相關的數(shù)據(jù)。庫管理系統(tǒng)中存取數(shù)據(jù)的，用C語言實現(xiàn)的，標準應用程序數(shù)據(jù)接口。論每個DBMS使用了何種數(shù)據(jù)存儲格式和編程接口。ODBC的結構包括四個主要部分：應用程序接口、驅動器管理器、數(shù)據(jù)庫驅動器和數(shù)據(jù)源。庫驅動器將修改應用程序的請求，使得請求符合相關的DBMS所支持的文法。是數(shù)據(jù)庫驅動器本身也執(zhí)行ODBC函數(shù)調用，并與數(shù)據(jù)庫相互配合。自從Java語言于1995年5月正式公布以來，Java風靡全球。這就使很多Java的優(yōu)秀特性無法充分發(fā)揮，的要求越來越強烈。也由于ODBC的有其不足之處，比如它并不容易使用，沒有面向對象。MIS管理人員喜歡Java和JDBC，因為這樣可以更容易經濟地公布信息。目前兩種基于JDBC的高層API. Javasoft和其他公司已經宣布要實現(xiàn)這一技術。

　　

【正文】 inter, and ODBC Medium Substantial use of indicators, including the highly error null pointer void *. Thus, Java programmers, the idea put JDBC to ODBC converted into objectoriented The API is very natural. 3) ODBC is not easy to study, it features easy and plex characteristics of mixed together, even for very simple query options are plex. The JDBC just Instead, it has maintained a simple and easy things, but the characteristics of the plex permit. 4) JDBC such JavaAPI for pure Java programs are necessary. When using ODBC, people must be on each client machine to install ODBC drivers and Driver Manager. If the JDBC driver to use Java language are fully realize, then the JDBC code can be automatically downloaded and installed, and to ensure their safety, Moreover, this will adapt to any Java platform, from the NC work puter to the mainframe Mainframe. All in all, JDBCAPI are able to embody the most basic abstraction of SQL, the most direct Java interface. It is the foundation to build on in the ODBC, therefore, familiar with the ODBC JDBC programmers will find very easy to study. JDBC has maintained the basic design features of ODBC. In fact, these two interfaces are based on X / OPENSQL the calllevel access I (CLI). Their biggest difference is that JDBC is based on the style and the advantages of Java and Java has strengthened the style and advantages. Recently, Microsoft also launched ODBC except outside the new API, such as RDO, ADO and OLEDB. These API in fact in many ways, like moving on with the JDBCphase The same direction, which is striving to bee an objectoriented, based on the type of ODBC interface. However, these interfaces is currently no substitute for ODBC, particularly in the ODBC Drive has been in the market, when fully formed, more importantly, they are only ODBC39。s beautiful packaging. 4. JDBC twotier model and the threetier model 山西大學本科畢業(yè)論文（設計）外文翻譯資料 JDBC support for a twotier model, also supported the threetier model for database access. Shown in Figure 3, a twotier model, a java Appple or a JAva application directly with the database connection. This need to be able to directly access the database Connect to the JDBC driver. The user39。s SQL statement transmitted to the database, and these statements will be sent the results of the implementation back to the user. Database can be in the same machine Up can also be another machine on the work to connect. This is known as Client / Server structure, the user39。s puter as a Client, run the database of Computer as Server. But this work intra, such as connecting all employees intra, of course, can also be inter. Shown in Figure 4, in the threetier model, the order will be sent to Service the middle layer, and middle layer will be sent to the database SQL statements. Database handle SQL statement and the results back, middle layer, then middle layer of their customers back. MIS administrators will find the threetier model very attractive because the middle Layer of the visit can control and coordination of the update database, another advantage is that if there is a middle layer users can use an easytouse highlevel The API, this API can be by the middle layer for conversion into the bottom of the call. Moreover, in many cases, the threetier model can provide better performance. So far, the middle layer is usually used C or C + + implementation, in order to guarantee its performance. However, with the introduction of piler optimization to java byte code conversion Into efficient machine code, using java to achieve middle layer will be more practical. And JDBC are a permit from the java middle layer the key to access the database.