php - User permissions custom cms -

looking advice on current setup , if there better approach (this first attempt @ building app this) @ point need user roles, 2 user , admin.

i have users table , groups table , join table takes id users table , id groups table , can allocate group user belongs too.

i wanting set way couple of things, prevent 'users' accessing admin area typing in url /admin/index.php , show link on index page if admin , not see it if normal user.

here code demonstrate can show users role title struggling @ point:

<?php $user = $_session['user'];     try{         $results = $dbh->query("select *                                 groups                                 inner join user_group_link_table                                 on groups.id = user_group_link_table.group_id                                 user_group_link_table.user_id = $user");  }catch(exception $e) {     echo $e->getmessage();     die(); }  $group = $results->fetchall(pdo::fetch_assoc);  foreach($group $groups){    echo         $groups["name"]       // show link admins user not see?     ;} ?> 

i wondering if approach totally wrong?

update

<? include('session.php'); if (!isset($_session['user'])) {   header("location: index.php"); } if(!ini_get('date.timezone')) {     date_default_timezone_set('gmt'); } // include file admin pages $isadmin = false; foreach($group $groups){     if($groups['name'] === 'admin'){         $isadmin = true;         break;     } }  if(!$isadmin){     header('location: index.php'); // or other arbitrary location     die(); } ?> 

and error:

notice: undefined variable: group in /applications/mamp/htdocs/dashboardr v3.2.3/admin/header.php on line 12

warning: invalid argument supplied foreach() in /applications/mamp/htdocs/dashboardr v3.2.3/admin/header.php on line 12

i wanting set way couple of things, prevent 'users' accessing admin area typing in url /admin/index.php , show link on index page if admin , not see it if normal user.

i'll give solution that'll work in current setup; it's not the way go, i'll job done now. if you're worried user being in specific role, you're better off specifying role in query rather iterating through potential roles.

// include file admin pages $isadmin = false; foreach($group $groups){     if($groups['name'] === 'admin'){         $isadmin = true;         break;     } }  if(!$isadmin){     header('location: index.php'); // or other arbitrary location     die; } 

you'll want place @ top of page, before spit out kind of html.