[問題] 初學連結資料庫發生錯誤

[i002149 (那年夏天)]

以下是一段從網路上找到的範例程式

範例原本會輸出
ID        Name        PASSWORD
1        yku        12356
2        yku2        7890

可是我執行的時候跑出以下異常

想請版上的高手幫忙看是哪方面出了錯誤



編輯環境
Eclipse
jdk1.6.0_23
hsqldb-2.0.1-rc3
win7 32bit
程式碼


package db;

//import org.hsqldb.jdbcDriver;
import java.sql.*;


public class Ooo
{
  private Connection con = null; //Database objects

  private Statement stat = null;
  private ResultSet rs = null;
  private PreparedStatement pst = null;

  private String dropdbSQL = "DROP TABLE User ";

  private String createdbSQL = "CREATE TABLE User (" +
    "    id     INTEGER " +
    "  , name    VARCHAR " +
    "  , passwd  VARCHAR)";

  private String insertdbSQL = "insert into User(id,name,passwd) " +
      "select nvl(max(id),0)+1,?,? FROM User";

  private String selectSQL = "select * from User ";

  public Ooo()
  {
    try {
      Class.forName("org.hsqldb.jdbcDriver");
      con = DriverManager.getConnection("jdbc:hsqldb:file:c:/database"
          , "SA", "");
    }
    catch(ClassNotFoundException e)
    {
      System.out.println("DriverClassNotFound :"+e.toString());
    }
    catch(SQLException x) {
      System.out.println("Exception :"+x.toString());
    }

  }

  public void createTable()
  {
    try
    {
      stat = con.createStatement();
      stat.executeUpdate(createdbSQL);
    }
    catch(SQLException e)
    {
      System.out.println("CreateDB Exception :" + e.toString());
    }
    finally
    {
      Close();
    }
  }

  public void insertTable( String name,String passwd)
  {
    try
    {
      pst = con.prepareStatement(insertdbSQL);

      pst.setString(1, name);
      pst.setString(2, passwd);
      pst.executeUpdate();
    }
    catch(SQLException e)
    {
      System.out.println("InsertDB Exception :" + e.toString());
    }
    finally
    {
      Close();
    }
  }

  public void dropTable()
  {
    try
    {
      stat = con.createStatement();
      stat.executeUpdate(dropdbSQL);
    }
    catch(SQLException e)
    {
      System.out.println("DropDB Exception :" + e.toString());
    }
    finally
    {
      Close();
    }
  }

  public void SelectTable()
  {
    try
    {
      stat = con.createStatement();
      rs = stat.executeQuery(selectSQL);
      System.out.println("ID\t\tName\t\tPASSWORD");
      while(rs.next())
      {
        System.out.println(rs.getInt("id")+"\t\t"+
            rs.getString("name")+"\t\t"+rs.getString("passwd"));
      }
    }
    catch(SQLException e)
    {
      System.out.println("DropDB Exception :" + e.toString());
    }
    finally
    {
      Close();
    }
  }

  private void Close()
  {
    try
    {
      if(rs!=null)
      {
        rs.close();
        rs = null;
      }
      if(stat!=null)
      {
        stat.close();
        stat = null;
      }
      if(pst!=null)
      {
        pst.close();
        pst = null;
      }
    }
    catch(SQLException e)
    {
      System.out.println("Close Exception :" + e.toString());
    }
  }
  public void shutdown() {

    try
    {
          stat = con.createStatement();
          stat.execute("SHUTDOWN");
              // if there are no other open connection
    }
    catch(java.sql.SQLException e)
    {
      System.out.println(e.toString());
    }
    finally
    {
      Close();
      if(con!=null)
      {
        try
        {
          con.close();
        }
        catch(java.sql.SQLException e)
        {
          System.out.println(e.toString());
        }
        con = null;
      }

    }
    }

  public static void main(String[] args)
  {
    Ooo test = new Ooo();
    test.dropTable();
    test.createTable();
    test.insertTable("yku", "12356");
    test.insertTable("yku2", "7890");
    test.SelectTable();
    test.shutdown();

  }
}

============================================

錯誤訊息

DropDB Exception :java.sql.SQLException: user lacks privilege or object not
found: USER in statement [DROP TABLE User ]
CreateDB Exception :java.sql.SQLException: length must be specified in type
definition: VARCHAR
InsertDB Exception :java.sql.SQLException: user lacks privilege or object not
found: USER
InsertDB Exception :java.sql.SQLException: user lacks privilege or object not
found: USER
DropDB Exception :java.sql.SQLException: user lacks privilege or object not
found: USER

--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 120.127.47.200
※ 編輯: i002149         來自: 120.127.47.200       (12/27 15:08)
→ tkcn:你看了錯誤訊息之後有什麼想法?
→ i002149:好像少了什麼物件 或者是使用者沒有權限
→ awert:錯誤訊息講得很明顯喔 ._. 快接近了
其實我沒有修過資料庫，但自JAVA期末專題老師又硬要我們連上資料庫，所以有些概念真
的不是很清楚，手邊有借了資料庫的書，但是是以MYSQL為例，所以有些地方不太一樣，
希望你們能夠幫忙...我也會繼續翻書找資料，感謝..
※ 編輯: i002149         來自: 61.224.48.4          (12/27 20:05)
→ i002149:換了一台電腦跑 順利跑出來了 但還是不知道原因...
→ tkcn:你原本那台電腦(的登入帳號)，有權限寫入 C:\ 嗎?
→ i002149:應該也是有權限...已經系統管理者登入...