在MyEclipse中执行模糊查询，ResultSet结果集不为空但rs.next()为false，求解。

Posted 2023-02-18

附代码：
HttpSession session = request.getSession(true); String t_id = (String) session.getAttribute("t_id");
List<Question> list = new ArrayList<Question>();
String condition = request.getParameter("condition");
String querySql;
if ("".equals(condition))
querySql = "select * from question1 where t_id=" + t_id;
else
condition = condition.trim();
querySql = "select * from question1 where ( question like '%"+ condition + "%' and t_id =" + t_id+")";

System.out.println(querySql);
Connection conn = MyDB.getConnection();
Statement stmt = MyDB.getStatement(conn);
ResultSet rs = MyDB.getResultSet(stmt,querySql);

if("".equals(rs))
System.out.println( "ResultSet结果集为空!");
else
try
while (rs.next())
Question q=new Question(); q.setId(rs.getInt("q_id"));
q.setQuestion(rs.getString("question"));
q.setChoice1(rs.getString("choice1"));
q.setChoice2(rs.getString("choice2"));
q.setChoice3(rs.getString("choice3"));
q.setChoice4(rs.getString("choice4"));
System.out.println(q.getId() + "--" + q.getQuestion() + "--"+ q.getChoice1() + "--" + q.getChoice2() + "--"+ q.getChoice3() + "--" + q.getChoice4() + "--");
list.add(q);
request.setAttribute("modifyQuestion", list);
request.getRequestDispatcher("/modify.jsp").forward(request,
response);
catch (SQLException e)
e.printStackTrace();


在mysql中该SQL语句执行正常

呵呵，这个问题太基础了啊，你这个restlet不为空，但是rs.next（）为空的原因是你查出来的数据只有一条，你debug跑到这块的时候已经执行过一次rs.next()了，然后你用watch一次rs.next()，肯定是false了啊，呵呵 参考技术A 、应该是MYSQL字符集的问题，查询的时候需要设置下字符集，具体的可以网上查下。