如何用SQL语句控制结果集的数目？

<%@ page language="java" import="java.sql.*" %>
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.lang.Math"%>
<jsp:useBean id="rencai2" scope="page" class="rencaixuqiu.database.rencai"/>
<%@ page errorPage="error.jsp"%>
<%!
    String getStr(String str)
    {
    try
    {
        String temp=new String(str.getBytes("ISO8859_1"));
    return temp;
    }
    catch(Exception e)
    {
    return null;
    }
}
%>
<%
   int quanxian=Integer.parseInt((String)session.getValue("quanxian"));
   String bumen=(String)session.getValue("department");
%>
<%
    String offset=null; //从URL中获得页面读取数据库记录的偏移量
    int count=0;        //总共的记录数
    int off=0;          //本页面的偏移量
    int page_cnt;       //总共的页面总数
    int pre_offset,page_offset,back_offset;
    String id=null;
    String sql=null;
    String msg=null;//得到返回的没有选择记录的提示消息，
     msg=getStr(request.getParameter("msg"));
     if(msg==null)
       msg="";
    rencai2.connect();    ResultSet RS=null;
     sql="select count(*)as count from nianzhongkaohebiao";
     try
       {
         RS=rencai2.executeQuery(sql);
         RS.next();
         count=Integer.parseInt(RS.getString("count"));
        }
     catch(SQLException e)
       {
         throw new SQLException("数据库读取错误");
       }
      //从URL中读取offset参数
    offset=request.getParameter("offset");
    if(offset==null)
       off=0;
    else
      off=Integer.parseInt(offset);


  %>
     <html><HEAD><TITLE>北京科锐星办公自动化信息系统</TITLE>
<META http-equiv=Content-Type content="text/html; charset=gb2312">
</HEAD>
<BODY bgColor=#ffffff leftMargin=2 topMargin=2 marginwidth="2" marginheight="2">
<SCRIPT language=JavaScript>

</SCRIPT><%@ include file="head.jsp" %><TABLE cellSpacing=0 cellPadding=0 width=773 border=0>
  <TBODY>
  <TR>
    <TD vAlign=top width=155>  <%@ include file="daohang.jsp" %>

     </TD>
    <TD width=10 height="467"> </TD>
    <TD vAlign=top align=middle width=815 height="467">
      <TABLE cellSpacing=0 cellPadding=0 width="810" border=0 height="411">
        <TBODY>
        <TR>
          <TD height=14 width="879"></TD></TR>
        <TR>
          <TD height="25" width="879"><font color="#FF0000" size="5" face="楷体_GB2312"><b>人事管理</b></font></TD></TR>
        <TR>
          <TD background=dot6.gif height=14 width="879">
            <hr style="border-style: dotted" color="#000080">
          </TD></TR>
        <TR>
          <TD height=30 width="879"><FONT color=#828383>首页>人事管理>
            </FONT><font color="#828383">公司培训信息></font><font color="#828383">年度年终考核表</font></TD></TR>
<TR>
          <TD height="20" width="879">
            <b><%=msg%></TD>
        </TR>
        <TR>
          <TD height="25" width="879">
            <P align="center"><b><font face="楷体_GB2312" size="5" color="#808000">公司员工年度年终考核表</font></b></P></TD>
        </TR>

        <tr>
          <TD height="317" width="879">
          <form method="POST" action="nzkh_control.jsp">
  <p align="center"><%
if((quanxian>40)||((quanxian>20)&&(bumen.equals("综合管理部")))){%>
<input type="submit" name="add" value="  填写  ">            
  <input type="submit" name="delete" value="  删除  ">
<%}%>
</p>


  <div align="left">
    <table border="0" width="882" height="33" bgcolor="#338899">
      <tr>
        <td width="146" height="25" align="center">
          <font color="#FFFFFF" face="楷体_GB2312"><b>序号</b></font>
        </td>
        <td width="146" height="25" align="center">
          <font color="#FFFFFF" face="楷体_GB2312"><b>姓名</b></font>
        </td>
    <td width="147" height="25" align="center">
          <font color="#FFFFFF" face="楷体_GB2312"><b>部门</b></font>
        </td>
      <td width="147" height="25" align="center">
          <font color="#FFFFFF" face="楷体_GB2312"><b>职务</b></font>
        </td>
        <td width="147" height="25" align="center">
          <font color="#FFFFFF" face="楷体_GB2312"><b>考核时间</b></font>
        </td>

        <td width="147" height="25" align="center">
          <font color="#FFFFFF" face="楷体_GB2312"><b>详细信息</b></font>
        </td>

      </tr>
<%
   sql="SELECT * FROM nianzhongkaohebiao order by bianhao DESC LIMIT "+off+",10";     RS=rencai2.executeQuery(sql);

    while(RS.next())
    { id=RS.getString("bianhao");
%>
<tr>
   <td align="center" width="146">
      <input type="checkbox"  name="pkeys" value=<%=id%>>
   </td>
<td align="center" width="146"><%=RS.getString("xingming")%></td>
<td align="center" width="147"><%=RS.getString("bumen")%></td>
<td align="center" width="147"><%=RS.getString("zhiwu")%></td>
<td align="center" width="142"><%=RS.getString("kaoheshijian")%></td>
<td align="center" width="142"><a href="nzkh_view_xx.jsp?id=<%=id%>"/>详细信息</td>
</tr><%}rencai2.disconnect();%> </table>
<p>
<p><center>
<%
    //使用分页技术，先判断是否是第一页，如是，则不显示上一页的连接
    if(off!=0)
       {
          pre_offset=off-10;
        out.println("<a href=\"nzkh_view.jsp?offset="+pre_offset+"\">上一页</a> \n");
        }
    page_cnt=(int)Math.ceil((double)count/10);
    for(int i=1;i<=page_cnt;i++)
       {
         page_offset=10*i-10;
         if(page_offset==off)
           out.println(i+"\n");
         else
        out.println("<a href=\"nzkh_view.jsp?offset="+page_offset+"\">"+i+"</a>\n");
       }
    //判断是否是最后一页，如是，则不显示下一页的连接
     if(page_cnt!=0 &&((off+10)/10)!=page_cnt)
        {
          back_offset=off+10;
           out.println("<a href=\"nzkh_view.jsp?offset="+back_offset+"\">下一页</a> \n");
        }
%><font color="#ff00bb" face="楷体_GB2312"><b>共有：<%=count%>条记录。</b></font>
</center>
    </div>
</form>          </TD>
        </tr>
        <tr>
          <TD height="12" width="879">
          </TD>
        </tr>
        <tr>
          <TD height="14" width="879">
          </TD>
        </tr>
        </TBODY></TABLE></TD></TR></TBODY></TABLE>
<%@ include file="copyright.jsp"%>

调试易

如何用SQL语句控制结果集的数目？

解决方案 »