Java SQL结果集检索顺序不正确

我的表中有以下三行说tb1

Hi I have the following three row in my table say tb1

key   time   id   rowid
X     11:40  1      1
Y     4:50   1      2
Z     6:48   1      2 

现在，我正在使用JDBC来获取记录并遍历结果集，如下所示:

Now I am using JDBC to get records and iterating over resultset as shown below:

rs = statement.executeQuery("select * from tb1")
ResultSetMetaData md = rs.getMetaData();
int cols = md.getColumnCount();
while(rs.next())
{
   for(int i = 1; i <= cols ; i++)
   {
     System.out.println("col name " + md.getColumnName(i));
     System.out.println("col name " + rs.getObject(i));
   }

}

当我奇怪地执行以上代码时，它总是先打印第二行，然后再打印第一行，然后再打印第三行.简而言之，结果集的数据检索不正确.我不明白为什么?请指导.预先感谢.

When I execute the above code strangely it always prints second row first and then first row and then third row. In short resultset data retrieval is not in order. I dont understand why? Please guide. thanks in advance.