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>> JDBC
>> Baisc Concepts about JDBC
由 george 发布于: 2001-03-02 13:50
<font size =10 color = blue>2-tier and 3-tier Database Access Models</font>
The JDBC provides support for 2-tier and 3-tier Database Access Models. WHen you use 2-tier access model, your java application talks directly to the database this is accomplished through the use of a JDBC dirver, which sends commands direactly to the database. THe results of these commands are then sent back from the database directly to the application.PLease see the following figure.
|-----------------------------|
| Application Space |
| |----------------| |
| | Java app | |
| | | |
| | | |
| |----------------| |
| |----------------| |
| | | |
| | Jdbc driver | |
| |----------------| |
|-----------------------------|
| A
SQL Command| | Result set
| |
V |
|----------------|
| DataBase |
|----------------|
The 3-tier model, as you might have guested, is a little more complicated, when you use the three tier midel, your JDBC driver sends commands to the database. The results of these commands are then sent back to the middle -tier, which communicates then back to the application.Just like the below:
|-----------------------------|
| Application Space |
| |----------------| |
| | Java app | |
| | | |
| | | |
| |----------------| |
| |----------------| |
| | | |
| | Jdbc driver | |
| |----------------| |
|-----------------------------|
| A
SQL Command| | Result set
| |
V |
|----------------------------|
| Appication Server |
| (Webspher or VisualAge |
| test enviornmentsDataBase |
| |
|----------------------------|
| A
| | proprietary protocols
| |
V |
|----------------|
| DataBase |
|----------------|
(followed by JDBC Driver Types)
How many kinds of JDBC driver in java?
Which one is most popular and is thought as the best one?
Whick kinds of driver sre there in Oralce Database?(you cannot find from books, tip: check the help documents of Oracle)
[已被 george 编辑过, 在 2001-03-02 16:39]
[已被 webmaster 编辑过, 在 2001-03-03 09:07]
[已被 webmaster 编辑过, 在 2001-03-03 09:15]
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资料来源: JSP001.com
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