Passing multiple IDs to the WHERE clause of an SQL query

[mmr315]

i wrote code like this

 
$Query1="select CarID from t_car_booking_info where PickupDate in('".$_POST['pickupdate']."','".$_POST['dropoffdate']."') and DropoffDate in('".$_POST['dropoffdate']."','".$_POST['pickupdate']."')";
$result1=mysql_query($Query1);
$nrows = mysql_num_rows($result1);
 
while($row=mysql_fetch_array($result1))
     { 
       for($i=0;$i<mysql_num_rows($result1);$i++) 
          {  
            $CarID=mysql_result($result1,$i,"CarID");  
          }
     $Query2="select * from t_car_info where CarID!='".$CarID."'";
    }
 
 
 

in that if query1 returns more than one carid how can i pass all carids at a time in the query2

[pbmods]

Heya, MMR.

Changed thread title to better describe the problem.

First off, instead of doing this:

while($row=mysql_fetch_array($result1))
     {
       for($i=0;$i<mysql_num_rows($result1);$i++)
          { 
            $CarID=mysql_result($result1,$i,"CarID"); 
          }
     $Query2="select * from t_car_info where CarID!='".$CarID."'";
    }
 

Get in the habit of doing this:

while($row=mysql_fetch_assoc($result1))
    {
     $CarID = $row['CarID'];
     $Query2="select * from t_car_info where CarID!='".$CarID."'";
    }
 

Try using MySQL's NOT IN subclause, combined with PHP's implode() builtin:

$_values = array();
while( $_row = mysql_fetch_assoc($result1) )
{
    $_values[] = $_row['CarID'];
}
mysql_free_result($result1);
 
$_sql = "
SELECT
        *
    FROM
        `t_car_info`
    WHERE
        `CarID`
            NOT
            IN
            (
                '" . implode("',\n\t\t\t\t'", $_values) . "'
            )";
$_res = mysql_query($_sql);