我正在尝试使用javamysql库，但我在使用准备好的语句时遇到问题。我不确定我缺少什么。下面是我在尝试使用准备好的语句时遇到的MYSQL错误。

String query = "SELECT id, clicks FROM mailer.links WHERE campaign_id=?";
    try {

        preparedStatement = connect.prepareStatement(query);
        preparedStatement.setInt(1, campaignId);
        preparedStatement.execute();
        Statement st = connect.createStatement();


        // execute the query, and get a java resultset
        ResultSet rs = st.executeQuery(query);

我收到以下错误：

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: 
You have an error in your SQL syntax; check the manual that corresponds to
your MySQL server version for the right syntax to use near '?' at line 1

它的工作原理，如果我做"campaign_id="活动ID，但SQL注入等待发生。