Question

我正在设计一个考勤系统。我在执行更新查询时遇到问题。这是代码

att.jsp

<%
String ID=request.getParameter("branch");
session.setAttribute("myUser", ID);
String Sid=request.getParameter("T1");
List<String> results = new ArrayList<String>();
List<String> name1 = new ArrayList<String>();
String sid,name;

%>
<%
  Class.forName("com.mysql.jdbc.Driver");
  Connection con = 
DriverManager.getConnection("jdbc:mysql://localhost:3306/sis","root","");
  Statement st=con.createStatement();
  st.executeUpdate("INSERT INTO attendancetb (SID,SName,branch) SELECT 
SID,SName,branch FROM student AS t1 WHERE NOT EXISTS (SELECT SID,SName FROM 
attendancetb AS t2 WHERE t1.SID = t2.SID)");
  ResultSet rs=st.executeQuery("select SID,SName from student where branch = 
'"+ID+"'");
  while(rs.next()){
      results.add(rs.getString(1));
      name1.add(rs.getString(2));
  }
%>
<FORM method="POST" ACTION="test1.jsp">
<table>
<% for(int i=0;i<results.size();i++){%>
<tr>
    <td>
        <%=results.get(i)%>
    </td>
    <td>
        <%=name1.get(i)%>
    </td>
<td> 
        <input TYPE=checkbox name=sports VALUE=<%=results.get(i)%>P>
</td>

<% } %>

</table>
<br> <INPUT TYPE=submit name=submit Value="Submit" >

test1.jsp

<%! String[] sports;
String[] x;%>
<% 
Class.forName("com.mysql.jdbc.Driver");
  Connection con= 
   DriverManager.getConnection("jdbc:mysql://localhost:3306/sis","root","");
  Statement st=con.createStatement();
  sports=request.getParameterValues("sports");
  if(sports!=null){
      for(int i=0;i<sports.length;i++){
          out.println ("<b>"+sports[i]+"<b>");
          st.executeUpdate("update attendancetb set attended = attended+1 
 where SID in ('"+sports[i]+"')");
      }
  }

    %>

在test1.jsp中，最后一条更新语句未得到执行，它在没有where条件的情况下工作。 out.println语句也将打印正确的值。请帮我。

更新查询未在JSP中执行

0 个答案: