Classe, datemi un parere

[StErMi]

<?
//include_once('config.inc.php');
class Admin {
    function Create_($var, $w) {
        $q = "INSERT INTO ";
        switch($w) {
            case 'news': $q .= "news";
            break;
            default: { echo "ciao"; }
        }
        $q .= " VALUES(''";
        foreach($var AS $v) {
            $v = trim(htmlspecialchars(nl2br($v)));
            $q .= ", '$v'";
        }        
        $q .= ")";
        //mysql_query($q, $db);
        echo $q;
    }
    function Show_($var, $w, $w2, $h, $lim) {
        $q = "SELECT ";
        if ( $var == "" ) $q .= "*";
        else {
            foreach( $var AS $v ) $q .= "$v, ";
            $q = substr($q, 0, strlen($q)-2);
        }
        $q .= " FROM $w";
        if ( $w2 != "" ) $q .= " WHERE $w2";
        if ( $h != "" ) $q .= " ORDER BY $h";
        if ( $lim != "" ) $q .= " LIMIT $lim";
        echo $q;
        //mysql_query($q, $db);
    }
    function Update_($var, $rep, $w, $w2) {
        $q = "UPDATE $w SET";
        $i = 0;
        while($i < count($var)) {
            $var[$i] = trim(htmlspecialchars(nl2br($var[$i])));
            $rep[$i] = trim(htmlspecialchars(nl2br($rep[$i])));
            $q .= " $var[$i] = '$rep[$i]',";
            $i++;
        }
        $q = substr($q, 0, strlen($q)-1);
        $q .= " WHERE $w2";
        echo $q;
        //mysql_query($q, $db);
    }
    function Delete_ ( $w, $w2 ) {
        $q = "DELETE FROM $w WHERE $w2";
        //mysql_query($q, $db);
    }
}
?>

lasciate perdere i particolari tipo lo switch nella prima funzione che sono piccolezze che devo modificare :P

qualche suggerimento?