在所有索引上的另一个数组的foreach迭代中迭代数组

PHP. I have two MySQL tables. I want to make fieldsets and checkboxes. I don't know how to use indexes.

buddies, with each a friend_id. assets, with each an asset_id, an asset_name, and a friend_id referring to you know what.

I know how to get through one index. I don't know how to do the rest.

print_r($buddies) echoes:

Array ( [0] => stdClass Object ( [friend_id] => Peter ) [1] => stdClass Object ( [friend_id] => Stephanie ) )

print_r($assets) echoes

Array ( [0] => Array ( [0] => stdClass Object ( [asset_id] => 39 [asset_name] => apple [friend_id] => Peter ) [1] => stdClass Object ( [asset_id] => 50 [asset_name] => pear [friend_id] => Peter ) [2] => stdClass Object ( [asset_id] => 51 [asset_name] => banana [friend_id] => Peter ) ) [1] => Array ( [0] => stdClass Object ( [asset_id] => 44 [asset_name] => apple [friend_id] => Stephanie ) ) )

My PHP code:

<?php 
 foreach ($buddies as $buddy) 
 {
     echo "<fieldset>";
     foreach ($assets as $asset)
     {
         if ($asset[0]->friend_id == $buddy->friend_id)
         {
             echo "<input value=\"".$asset[0]->asset_id."\">". $asset[0]->asset_name . "</input>";
         }
     }
     echo "</fieldset>";
 }