//聲明本類包含在包examples.jdbc.oracle中
package examples.jdbc.oracle;
//聲明本類要引入的其他包和類
import java.sql.*;
import java.util.Properties;

/**
 * 這個實例演示如何用JDBC查詢數(shù)據(jù)和結(jié)果集。 
 */

public class simpleselect {
  
  public static void main(String argv[])
       throws Exception
  {
  //聲明屬性變量	
    Properties props = new Properties();
    props.put("user","scott");
    props.put("password","tiger");
    props.put("server","DEMO");
	//加載數(shù)據(jù)庫驅(qū)動程序weblogic.jdbc.oci.Driver
    Driver myDriver = (Driver) Class.forName("weblogic.jdbc.oci.Driver").newInstance();
      //創(chuàng)建連接，連接數(shù)據(jù)庫jdbc:weblogic:oracle
    Connection conn = myDriver.connect("jdbc:weblogic:oracle", props);
    //創(chuàng)建SQL語句對象stmt
    Statement stmt = conn.createStatement();
    //執(zhí)行SQL語句，查詢表empdemo中的所有記錄
        stmt.execute("select * from empdemo");
    	//獲取結(jié)果集
        ResultSet rs = stmt.getResultSet();
    
    //也可以直接用    ResultSet rs = stmt.executeQuery("select * from empdemo");
    //打印查詢結(jié)果，打印所有記錄
    while (rs.next()) {
      System.out.println(rs.getString("empid") + " - " + 
                         rs.getString("name")  + " - " + 
                         rs.getString("dept"));
    }
    //獲取數(shù)據(jù)集元數(shù)據(jù)對象
    ResultSetMetaData rsmd = rs.getMetaData();
    //獲取列數(shù)并打印
    System.out.println("Number of Columns: " + rsmd.getColumnCount());
    //獲取并打印表結(jié)構(gòu)信息
    for (int i = 1; i <= rsmd.getColumnCount(); i++) {
      System.out.println("Column Name: "          + rsmd.getColumnName(i));
      System.out.println("Nullable: "             + rsmd.isNullable(i));
      System.out.println("Precision: "            + rsmd.getPrecision(i));
      System.out.println("Scale: "                + rsmd.getScale(i));
      System.out.println("Size: "                 + rsmd.getColumnDisplaySize(i));
      System.out.println("Column Type: "          + rsmd.getColumnType(i));
      System.out.println("Column Type Name: "     + rsmd.getColumnTypeName(i));
      System.out.println("");
    }
    //關閉
    stmt.close();
    conn.close();
  }
}