When PHP exports large amounts of Excel data

 Public functionCeshiexcel1 () {Set_time_limit(0); $filename= ' Virus log '; Header(' Content-type:application/vnd.ms-excel '); Header(' Content-disposition:attachment;filename= '.$filename.‘. CSV "'); Header(' Cache-control:max-age=0 '); //native link MySQL//database configuration        $mysql _conf=Array(' host ' = ' 127.0.0.1:52971 ', ' db ' = ' center ', ' db_user ' = ' root ', ' db_pwd ' and ' = '); $mysql _conn= @mysql_connect($mysql _conf[' Host '],$mysql _conf[' Db_user '],$mysql _conf[' Db_pwd ']); if(!$mysql _conn) {             die("Could not connect to the database:\n".Mysql_error());//Diagnosing Connection Errors        }        $select _db=mysql_select_db($mysql _conf[' DB ']); if(!$select _db) {             die("Could not connect to the db:\n".Mysql_error()); }        $sql= M (' Logvirus ')                    ->alias (' a ')                     -Fetchsql ()->field (' A.id,a.strvirusname,c.address,c.rmaker,a.nvirustype,a.nunknowvirustype,a.strviruspath,a.virustime,  A.nunknownflag,a.terminal,d.name as Rname, (case if A.ihigh_disktype=0 then A.ilow_disktype else A.ihigh_disktype end) As Idisktypes ')//F.idisktypes,j.name as Iname-Join(' left JOIN sysinfo c on c.terminal = A.terminal ')                    -Join(' left JOIN pm_dealresult d on d.mask = A.ndealresult ')                     //->where ($where)->order ("A.virustime desc")                    ->limit (' 1,10 ')                    -Select (); $head=Array(                    ' id ' = ' + ' number ', ' strvirusname ' + ' virus name ', ' address ' = ' ip ', ' Rmaker ' = ' + ' Alias ', ' nname ' = ' virus type ', ' iname ' + ' threat source ', ' strvir Uspath ' + ' virus path ', ' rname ' = ' processing result ', ' virustime ' = ' time ' ); $stmt=mysql_query($sql); /*echo "<pre/>";                              while ($row = Mysql_fetch_array ($stmt, Mysql_assoc)) {foreach ($row as $i = = $v) {                   $row [$i] = iconv (' utf-8 ', ' gb2312 ', $v);        Var_dump ($row); }} exit;*/        //open php file handle, php://output direct output to browser         $fp=fopen(' Php://output ', ' a '); //output Excel Column name information//$head = array (' id ', ' casenum ', ' terminal ', ' strVirusMd5 ', ' nvirustype ', ' nviruscode ', ' Noldvirus '  Code ');         foreach($head  as $i=$v) {              //CSV Excel support GBK encoding, be sure to convert otherwise garbled            $head[$i] =Iconv(' Utf-8 ', ' gb2312 ',$v); }         //writes data to a file handle via FputcsvFputcsv ($fp,$head); //counter        $cnt= 0; //every $limit line, refresh the output buffer, not too big, not too small        $limit= 100000; //row-by-line data extraction without wasting memory        $data=Array();  while($row=Mysql_fetch_array($stmt,Mysql_assoc)) {              $cnt++; if($limit==$cnt) {//Refresh the output buffer to prevent problems caused by too much data                Ob_flush();//Release                Flush(); $cnt= 0; }                                 foreach($row  as $i=$v) {                  //$row [$i] = iconv (' utf-8 ', ' gb2312 ', $v);                   $data[' id '] =$cnt; $data[' strvirusname '] =Iconv(' Utf-8 ', ' gb2312 ',$row[' Strvirusname ']); $data[' address '] =Iconv(' Utf-8 ', ' gb2312 ',$row[' Address ']); $data[' rmaker '] =Iconv(' Utf-8 ', ' gb2312 ',$row[' Virustime ']); $data[' nname '] =Iconv(' Utf-8 ', ' gb2312 ',$row[' Virustime ']); $data[' iname '] =Iconv(' Utf-8 ', ' gb2312 ',$row[' Virustime ']); $data[' strviruspath '] =Iconv(' Utf-8 ', ' gb2312 ',$row[' Virustime ']); $data[' rname '] =$row[' Rname '] ; $data[' virustime '] =Iconv(' Utf-8 ', ' gb2312 ',$row[' Virustime ']); } fputcsv ($fp,$data); }    //Close the database     Mysql_close($mysql _conn); }

When PHP exports large amounts of Excel data