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<?php $arr = [ ['comment_id' => 32, 'article_id' => 5, 'parent_id' => 31, 'user_id' => 22, 'content' => 'dolor sit amet consectetur adipisicing', 'created_at' => '02-04-2021'], ['comment_id' => 30, 'article_id' => 5, 'parent_id' => 29, 'user_id' => 22, 'content' => 'Lorem ipsum dolor sit amet.', 'created_at' => '01-04-2021'], ['comment_id' => 31, 'article_id' => 5, 'parent_id' => 29, 'user_id' => 22, 'content' => 'Sit amet consectetur adipisicing', 'created_at' => '02-04-2021'], ['comment_id' => 29, 'article_id' => 5, 'parent_id' => 0, 'user_id' => 22, 'content' => 'dolor sit amet consectetur adipisicing', 'created_at' => '01-04-2021'] ]; $arr_by_comment_id = array_column($arr, null, 'comment_id'); $root_entry = null; foreach ($arr_by_comment_id as &$entry) { if ($entry['parent_id'] === 0) { $root_entry =& $entry; } elseif (array_key_exists($entry['parent_id'], $arr_by_comment_id)) { $arr_by_comment_id[$entry['parent_id']]['comments'][] = $entry; } } unset($entry); // For safety (after reference looping) print_r($root_entry);
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.4, 8.3.6 - 8.3.26, 8.4.1 - 8.4.13
Array ( [comment_id] => 29 [article_id] => 5 [parent_id] => 0 [user_id] => 22 [content] => dolor sit amet consectetur adipisicing [created_at] => 01-04-2021 [comments] => Array ( [0] => Array ( [comment_id] => 30 [article_id] => 5 [parent_id] => 29 [user_id] => 22 [content] => Lorem ipsum dolor sit amet. [created_at] => 01-04-2021 ) [1] => Array ( [comment_id] => 31 [article_id] => 5 [parent_id] => 29 [user_id] => 22 [content] => Sit amet consectetur adipisicing [created_at] => 02-04-2021 [comments] => Array ( [0] => Array ( [comment_id] => 32 [article_id] => 5 [parent_id] => 31 [user_id] => 22 [content] => dolor sit amet consectetur adipisicing [created_at] => 02-04-2021 ) ) ) ) )
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 Array ( [comment_id] => 29 [article_id] => 5 [parent_id] => 0 [user_id] => 22 [content] => dolor sit amet consectetur adipisicing [created_at] => 01-04-2021 [comments] => Array ( [0] => Array ( [comment_id] => 30 [article_id] => 5 [parent_id] => 29 [user_id] => 22 [content] => Lorem ipsum dolor sit amet. [created_at] => 01-04-2021 ) [1] => Array ( [comment_id] => 31 [article_id] => 5 [parent_id] => 29 [user_id] => 22 [content] => Sit amet consectetur adipisicing [created_at] => 02-04-2021 [comments] => Array ( [0] => Array ( [comment_id] => 32 [article_id] => 5 [parent_id] => 31 [user_id] => 22 [content] => dolor sit amet consectetur adipisicing [created_at] => 02-04-2021 ) ) ) ) )
preferences:
146.41 ms | 414 KiB | 5 Q