使用JDBC读取数据库

Question

我在其中一个程序中使用JDBC和SQLite创建了一个表。现在，我试图从数据库中读取特定的值。我正在尝试获取最后的订单号，但出现错误。我把我的代码放在下面。不知道出了什么问题：

try {
    String sql = "SELECT ordernumber FROM orderTable ORDERBY ordernumber LIMIT 1 DESC";
    Connection connection = DriverManager.getConnection(url);
    Statement stmt = connection.createStatement();
    ResultSet rs = stmt.executeQuery(sql);
    System.out.println(rs.getInt("ordernumber"));
} catch (SQLException e) {
    System.out.println(e.getMessage());
}

Answer 1

更改

String sql = "SELECT ordernumber FROM orderTable ORDERBY ordernumber LIMIT 1 DESC";

到

String sql = "SELECT ordernumber FROM orderTable ORDER BY ordernumber LIMIT 1 DESC";

Answer 2

也许您可以将SQL更新为正确的语法，然后运行它。

String sql = "SELECT ordernumber FROM orderTable ORDERBY ordernumber LIMIT 1 DESC";

（右一个）：

String sql = "SELECT ordernumber FROM orderTable ORDER BY ordernumber DESC LIMIT 1 ";