jdbc连接数据库代码笔记简单易懂niiT培训.doc

package com.niit;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class JDBCExamplepublic static void main(String args)Connection conn = null;Statement stmt = null;ResultSet rs = null;/ 1、加载驱动程序类new oracle.jdbc.driver.OracleDriver();try/ 2、得到一个数据库的链接conn = DriverManager.getConnection(jdbc:oracle:thin:9:1521:recruit, user30,user30);/ 3、得到Statement，真正执行SQL语句的stmt = conn.createStatement();/ 4、进行查询，得到结果集rs = stmt.executeQuery(select * from country);/ 5、遍历结果集，进行显示while (rs.next()System.out.print(code: + rs.getString(1);System.out.print(tcountry: + rs.getString(2);System.out.println();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();finallytryif (rs != null)rs.close();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();tryif (stmt != null)stmt.close();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();tryif (conn != null)conn.close();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();第二种连接数据库的方式：ODBCJDBCAppODBCOpen DataBase ConnectivityJDBCJava DataBase ConnectivityDriver 驱动类的接口DriverManager，驱动程序管理器类。提供对数据库驱动程序的管理功能首先准备驱动程序，加载到内存中，就会自动注册到manager内当我们连接和操作的过程中就会自动调用底层的数据库的驱动程序Connection接口，表示一个连接Statement接口，实际上可以认为就是拥有真正执行SQL的功能的对象ResultSet接口，结果集，封装了查询结果，可以对其进行遍历JDBC连接方式四种：1、使用相关的数据库协议直连数据库（thin）。速度快，最直接。需要一份驱动程序2、JDBC-ODBC桥式驱动。不需要准备驱动程序，较方便。有平台依赖性。3、Java到本地API。（OCI）将JDBC的调用指令变换为对本地的数据库工具的API的调用需要在本地上安装目标数据库的客户端程序4、以与数据库无关的网络协议的方式发送JDBC调用，数据库服务器端需要安装中间件数据库URL用于标识目标数据库主协议名 ： 子协议名 ： 子名称jdbc ：oracle:thin:9：1521：recruitjdbc : mysql :/9:3306/dbname加载驱动的三种方式：连接多个数据库驱动用冒号，下面是三种方式：在JDBC里，数据库是默认autocommit执行的/* 通过jdbc:odbc:drive创建一个数据库连接实例 */ public void creatConnectInstance() String strurl=jdbc:odbc:driver=Microsoft Access Driver (*.mdb);DBQ=C:pmis.mdb; try Class.forName(sun.jdbc.odbc.JdbcOdbcDriver); conn = DriverManager.getConnection(strurl); stmt = conn.createStatement(); catch(Exception e) System.out.println(e.getMessage(); 完整实例JDBCExample.javapackage com.niit;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class JDBCExamplepublic static void main(String args)Connection conn = null;Statement stmt = null;ResultSet rs = null;/ 1、加载驱动程序类/ new oracle.jdbc.driver.OracleDriver();try/ Class.forName(oracle.jdbc.driver.OracleDriver);System.setProperty(jdbc.drivers,oracle.jdbc.driver.OracleDriver:+ com.microsoft.jdbc.sqlserver.SQLServerDriver);/ 2、得到一个数据库的链接conn = DriverManager.getConnection(jdbc:oracle:thin:9:1521:recruit, user30,user30);/ 3、得到Statement，真正执行SQL语句的stmt = conn.createStatement();/ 4、进行查询，得到结果集rs = stmt.executeQuery(select * from country);/ 5、遍历结果集，进行显示while (rs.next()System.out.print(code: + rs.getString(1);System.out.print(tcountry: + rs.getString(2);System.out.println();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();/ catch (ClassNotFoundException e)/ / / TODO Auto-generated catch block/ e.printStackTrace();/ finallytryif (rs != null)rs.close();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();tryif (stmt != null)stmt.close();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();tryif (conn != null)conn.close();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();TestDDL.javapackage com.niit;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class TestDDL/* * param args */public static void main(String args)tryClass.forName(oracle.jdbc.driver.OracleDriver);String url = jdbc:oracle:thin:9:1521:recruit;Connection conn = DriverManager.getConnection(url, user30,user30);Statement stmt = conn.createStatement();stmt.execute(create table myCountry(ccountrycode char(4),ccountry varchar2(10);stmt.executeUpdate(insert into mycountry values(001,中华民国);ResultSet rs = stmt.executeQuery(select * from mycountry);while (rs.next()System.out.print(code: + rs.getString(1);System.out.print(tcountry: + rs.getString(2);System.out.println();rs.close();stmt.close();conn.close();catch (ClassNotFoundException e)/ TODO Auto-generated catch blocke.printStackTrace();catch (SQLException e)/ TODO Auto-generated catch blocke.printStackTrace();TestDML.javapackage com.niit;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class TestDMLpublic static void main(String args)Connection conn = null;tryClass.forName(oracle.jdbc.driver.OracleDriver);String url = jdbc:oracle:thin:9:1521:recruit;conn = DriverManager.getConnection(url, user30,user30);Statement stmt = conn.createStatement();stmt.executeUpdate(insert into country values(091,魏);stmt.executeUpdate(insert into country values(092,蜀);stmt.executeUpdate(insert into country values(093,吴);ResultSet rs = stmt.executeQuery(select * from country);while (rs.next()System.out.print(code: + rs.getString(1);System.out.print(tcountry: + rs.getString(2);System.out.println();rs.close();System.out.println(-我是华丽的分隔线-);conn.setAutoCommit(false);stmt.executeUpdate(update country set ccountry=晋 where ccountrycode=091);stmt.executeUpdate(delete from country where ccountrycode=092 or ccountrycode=093);mit();rs = stmt.executeQuery(select * from country);while (rs.next()System.out.print(code: + rs.getString(1);System.out.print(tcountry: + rs.g