PHP - 出乎意料吗？ [关闭]

When I try to execute the code, I get an error saying unexpected 'While'. Any idea on where I'm going wrong here? I'm attempting to only let a user bid if they aren't already the highest bidder. All was well until I tried adding in my if... else statement.

<?php
session_start();
require_once("dbconnect.inc");

$accountid=$_SESSION['accountid'];
$itemid=$_POST['itemid'];

mysql_query("SELECT accountid FROM bidhistory 
WHERE biditem = '$itemid' ORDER BY bidhistoryid DESC");

$result=mysql_query($sql)

while($row = mysql_fetch_array($result)){
  $checkaccountid = $row['accountid']; 

if($checkaccountid == $accountid){ 
echo "You are the highest bidder!";
}

else {
$sql="INSERT INTO bidhistory (accountid, biditemid)
VALUES ($accountid, $itemid)"; 

mysql_query("
UPDATE bidhistory
SET bidprice = bidprice + 1
WHERE biditemid = " .
@mysql_escape_string($itemid));

$result=mysql_query($sql) or die("Error in adding bid for item: ".mysql_error());
  }
}
?>

Need to add semicolon to

$result=mysql_query($sql)

so...

$result=mysql_query($sql);