jdbcdemo.java

ODBC数据库连接

/*ODBC数据库连接  

 

 
   /* 
 * @(#)JDBCDemo.java 2000/06/18 
 */ 
import java.sql.*; 

public class JDBCDemo  
{ 
       public static void main(String args[])  
         { 
               try { 
                        Statement stmt; 
                        PreparedStatement pstmt; 
                        ResultSet rs; 
                        
                        // 加载 jdbc-odbc 桥驱动程序 
                        Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); 

                        //定义JDBC URL 
                        String url   = "jdbc:odbc:BookDB";//BookDB为数据源名 

                        //得到与数据库的连接 
                        Connection con = DriverManager.getConnection (url); 

                        //显示URL和连接信息 
                        System.out.println("URL: " + url); 
                        System.out.println("Connection: " + con); 

                        //得到一个Statement对象 
                        stmt = con.createStatement(); 

                      /*  //如果表DemoTable已经存在，则删除之，否则，抛掷一个异常 
                        System.out.println("DROP TABLE DemoTable, if it exists."); 
                        try{ 
                                 stmt.executeUpdate("DROP TABLE DemoTable"); 
                        }catch(Exception e){ 
                                 System.out.print(e); 
                                 System.out.println("No existing table to delete"); 
                        } */

                       //在数据库中创建一个表DemoTable 
                       stmt.executeUpdate("CREATE TABLE DemoTable (" 
                                    + "test_id int,test_val char(15) not null)"); 
                       System.out.println("table DemoTable created!"); 

                      /* //在表中插入一些值 
                       stmt.executeUpdate("INSERT INTO DemoTable (" 
                                  + "test_id, test_val) VALUES(1,'One')"); 
                       stmt.executeUpdate("INSERT INTO DemoTable (" 
                                  + "test_id, test_val) VALUES(2,'Two')"); 
                       stmt.executeUpdate("INSERT INTO DemoTable (" 
                                  + "test_id, test_val) VALUES(3,'Three')"); 
                       stmt.executeUpdate("INSERT INTO DemoTable (" 
                                  + "test_id, test_val) VALUES(4,'Four')"); 
                       stmt.executeUpdate("INSERT INTO DemoTable (" 
                                  + "test_id, test_val) VALUES(5,'Five')"); 

                       //得到另一个Statement对象 
                       stmt = con.createStatement(); 

                       //查询数据库中的表DemoTable，得到以test_id排序后的所有记录， 
                       //并存储在ResultSet对象rs中 
                       rs = stmt.executeQuery("SELECT * from DemoTable ORDER BY test_id"); 

                      //显示表DemoTable中的所有记录 
                       System.out.println("Display all results:"); 
                       while(rs.next()) 
                           { 
                             int theInt= rs.getInt("test_id"); 
                             String str = rs.getString("test_val"); 
                             System.out.println("\ttest_id= " + theInt + "\tstr = " + str); 
                       } 

                      // 创建已准备好的语句，更新“DemoTable”表中 
                      // 某条记录的test_val字段。 
                      // 已准备好的语句接受两个参数。 
                      pstmt = con.prepareStatement( 
                                 "UPDATE DemoTable SET test_val = ? WHERE test_id = ?"); 


                      //更改表DemoTable中的第2条记录的test_val字段的值 
                      // 充填UPDATE语句中的“？”，并执行UPDATE语句 
                      pstmt.setString(1, "Hello!"); 
                      pstmt.setInt(2, 2); 
                      pstmt.executeUpdate(); 
                      System.out.println("Update row number 2: OK."); 

                      //显示表DemoTable中更新后的第2条记录 
                      stmt = con.createStatement(); 
                      rs = stmt.executeQuery("SELECT * from DemoTable ORDER BY test_id"); 
                      System.out.println("Display row 2:"); */
                     /* if (rs.next() && rs.next()) 
                        { 
                           int theInt= rs.getInt("test_id"); 
                           String str = rs.getString("test_val"); 
                           System.out.println("\ttest_id= " + theInt + "\tstr = " + str); 
                        } */

                              con.close(); //关闭与数据库的连接 
                      }catch( Exception e ) { 
                              e.printStackTrace(); 
                      } 
     } 
}