ECHO of an object breaking page - php

Question

I have the following code that when used breaks my page. What am I not doing correctly?
$check_availability = $wpdb->get_results($wpdb->prepare("SELECT id FROM mytablename "));
foreach ($check_availability as $available){
echo $available . "<br>\n";
}
Ive tried moving the echo out of the loop. Same broken page result. This worked correctly when I had NO foreach loop at all but then it would only return 1 result instead of many.
EDIT 1 to show var_dump($available) result inside the loop -
object(stdClass)#2314 (1) { ["id"]=> string(1) "4" } object(stdClass)#2361 (1) { ["id"]=> string(1) "6" }
If I var_dump($check_availability ) outside of the loop then I get
array(2) { [0]=> object(stdClass)#2314 (1) { ["id"]=> string(1) "4" } [1]=> object(stdClass)#2361 (1) { ["id"]=> string(1) "6" } } array(2) { [0]=> object(stdClass)#2314 (1) { ["id"]=> string(1) "4" } [1]=> object(stdClass)#2361 (1) { ["id"]=> string(1) "6" } }

Answer 1

The "echo" function can only print strings / numbers.
In this case you are trying to print an object.
If you want to print the id try writing:
$check_availability = $wpdb->get_results($wpdb->prepare("SELECT id FROM mytablename "));
foreach ($check_availability as $available){
echo $available->id . "<br>\n";
}
If you are interested in knowing what '$available' contains, run this:
$check_availability = $wpdb->get_results($wpdb->prepare("SELECT id FROM mytablename "));
foreach ($check_availability as $available){
var_dump($available);
}