计数已删除的记录,返回0

我执行 DELETE 通过调用一个方法从我的servlet在我的表中 action.deleteBox(box); 执行删除功能

deleteBox方法

Connection c = null;
PreparedStatement stm = null;
sq = "DELETE FROM BOXES WHERE ...";

try {       
    Class.forName(typeDB);
    c = DriverManager.getConnection(path);    
    stm = c.prepareStatement(sq);
    //...
    stm.executeUpdate();

} catch (SQLException e) {             
    System.out.println(e.getMessage());
} finally {
        System.out.println("my stm is closed : " + stm.isClosed());
        if (stm != null)
                    stm.close();
        if (c != null)
                    c.close();
}

删除被良好地执行。然后我想检查上次删除中删除了多少条记录:所以我调用这个方法:

public int countDeletesRecords() 
        throws SQLException, ClassNotFoundException {

    Connection c = null;
    PreparedStatement stm = null;
    sq = "SELECT changes() as \"deletedRows\" ";
    int deletedRows=-1;

    try {       
        Class.forName(typeDB);
        c = DriverManager.getConnection(path);    
        stm = c.prepareStatement(sq);       
        ResultSet rs = stm.executeQuery();

        if (rs.next()) {
            deletedRows = rs.getInt("deletedRows");
        }

    } catch (SQLException e) {             
        System.out.println(e.getMessage());
    } finally {
        System.out.println("my stm is closed : " + stm.isClosed());
        if (stm != null)
            stm.close();
        if (c != null)
            c.close();
    } 

    return deletedRows; //I get 0..
}

我得到0,而1条记录被删除。