Sql query in MySql_Fetch_Array

When i show this php on browser i couldn't get any value to table. My table is empty.

<?php 

    $sql = "select * from worksets where 'groupid'='$targetid'";
    $query = mysql_query($sql);

    $kadro=$_GET['kadro'];

    if((mysql_num_rows($query) > 0)) {
        while($result = mysql_fetch_array($query)) {
            $groupid =  $result[0];
            $groupname = $result[2];
            $sql2 = "select flag from havestatus where kadroid='$kadro' and yid='$groupid'";
            $query2 = mysql_query($sql2);

            if((mysql_num_rows($query2) == 0)) {
                $sql3 = "insert into havestatus values('$kadro','$yid',0)";
            } else {
                $select='selected';
            }
            ?>
            <tr>
                <td width='50%'><?php echo $groupname;?></td>
                <td></td>
                <td width='20%'><input type="checkbox" name="bev" checked="<?php echo $select; ?>"></td>
            </tr>
            <?php
        }
    }
?>

If i change code in simple way like;

It shows some values and unfunctional checkbox.

I need to get some values from database and fill checkboxs according to 0 or 1 from database and i have to insert all check box values with one form submit button to database as different rows for every check box

<?php 

    $sql = "select * from worksets where groupid='$targetid'";
    $query = mysql_query($sql);

    if((mysql_num_rows($query) > 0)) {
        while($result = mysql_fetch_array($query)) {
            $groupid =  $result[0];
            $groupname = $result[2];
            ?>

            <tr>
                <td width='50%'><?php echo $groupname;?></td>
                <td></td>
                <td width='20%'><input type="checkbox" name="bev"></td>    
            </tr>
            <?php
        }
    }
?>

it is work after 'groupid'='$targetid'" to groupid='$targetid'"