3v4l.org

run code in 500+ PHP versions simultaneously
<?php $arr=array(); $arr[0]['id']='123'; $arr[0]['otherdatas']=''; $arr[1]['id']='234'; $arr[1]['otherdatas']=''; $arr[2]['id']='567'; echo implode(',',array_column($arr,'id'));

preferences:
57.65 ms | 1969 KiB | 5 Q