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<?php $json = '[{"_id":"123","books":[{"author":"John","title":"The Book"},{"author":"Smith","title":"Something!"}]},{"_id":"321","books":[{"author":"John","title":"The Book"}]}]'; $array = json_decode($json, 1); $ids = []; foreach($array as $v) { foreach($v['books'] as $book){ $books[] = $book; } } print_r($books); echo json_encode($books); ?>
Output for 7.1.25 - 7.1.33, 7.2.0 - 7.2.33, 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 - 8.3.25, 8.4.1 - 8.4.12
Array ( [0] => Array ( [author] => John [title] => The Book ) [1] => Array ( [author] => Smith [title] => Something! ) [2] => Array ( [author] => John [title] => The Book ) ) [{"author":"John","title":"The Book"},{"author":"Smith","title":"Something!"},{"author":"John","title":"The Book"}]
preferences:
175.01 ms | 409 KiB | 5 Q