$sql = "SELECT SUBSTRING(SUBSTRING_INDEX(`COLUMN_TYPE`,'\')',1),6) as set_str FROM `information_schema`.`COLUMNS` WHERE `TABLE_SCHEMA` = 'db' AND `TABLE_NAME` = 'tbl' AND `COLUMN_NAME` = 'col'";
    $set_h = mysqli_query($c,$sql);
    if (!$set_h){  
       echo  "ERROR: ".$sql;
       return;
    }
    if (mysqli_num_rows($set_h)!=0){
        $set_str = mysql_result($set_h,0,'set_str');
        echo $set_str.'<br>';
        $type_a = explode("','",$set_str);
        print_r($type_a);
    }
    return;