Only Specified Extension With Size Can Upload?

Dear all i have a problem, how to do this with sql/php
i have the following table structure. how to allow PHP upload file to upload only these extension having their respective size.

 

$filetype = $_FILES['filefield']['type'];
$q= ("select * from yourtablename where extension='$filetype' limit 1");
$res= mysql_query($q) or die(mysql_error());
if (mysql_num_rows($res)==0) {
//it means file type not present in your table
echo "File type not allowed !";
} else {
//this size is in byte, to use Kb or MB divide it ot 1024. example for mb : $mbfilesize = ($_FILES['filefield']['size']/1024)/1024;
$filesize = $_FILES['filefield']['size'];
while ($row=mysql_fetch_assoc($res)) { 
$tblsize = $row['size'];
}
if ($filesize>$tblsize) { echo "Maximum file size allowed : ".$tblsize;} else { //continue upload }
}

Code (markup):

hope this helps you get the idea!

 

Thank you very much bledileka, problem solved