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<?php $bookInfo = array( 0 => array("bookId" => "1", "bookName" => "Book 1", "authorId" => 1, "authorName" => "Author 1") , 1=> array("bookId" => "1", "bookName" => "Book 1", "authorId" => 2, "authorName" => "Author 2") , 2=> array("bookId" => "2", "bookName" => "Book 2", "authorId" => 3, "authorName" => "Author 3") , 3=> array("bookId" => "3", "bookName" => "Book 3", "authorId" => 4, "authorName" => "Author 4") ); print_r($bookInfo); $newBookInfo = []; $newBookKey = []; $newKey = 0; foreach($bookInfo as $bookKey => $bookValue){ if(!in_array($bookValue["bookId"],$newBookKey)){ ++$newKey; $newBookInfo[$newKey]["bookId"] = $bookValue["bookId"]; $newBookInfo[$newKey]["bookName"] = $bookValue["bookName"]; } $newBookInfo[$newKey]["authorName"][$bookKey] = $bookValue["authorName"]; $newBookKey[] = $bookValue["bookId"]; } print_r($newBookInfo);
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
Array ( [0] => Array ( [bookId] => 1 [bookName] => Book 1 [authorId] => 1 [authorName] => Author 1 ) [1] => Array ( [bookId] => 1 [bookName] => Book 1 [authorId] => 2 [authorName] => Author 2 ) [2] => Array ( [bookId] => 2 [bookName] => Book 2 [authorId] => 3 [authorName] => Author 3 ) [3] => Array ( [bookId] => 3 [bookName] => Book 3 [authorId] => 4 [authorName] => Author 4 ) ) Array ( [1] => Array ( [bookId] => 1 [bookName] => Book 1 [authorName] => Array ( [0] => Author 1 [1] => Author 2 ) ) [2] => Array ( [bookId] => 2 [bookName] => Book 2 [authorName] => Array ( [2] => Author 3 ) ) [3] => Array ( [bookId] => 3 [bookName] => Book 3 [authorName] => Array ( [3] => Author 4 ) ) )
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 ( [0] => Array ( [bookId] => 1 [bookName] => Book 1 [authorId] => 1 [authorName] => Author 1 ) [1] => Array ( [bookId] => 1 [bookName] => Book 1 [authorId] => 2 [authorName] => Author 2 ) [2] => Array ( [bookId] => 2 [bookName] => Book 2 [authorId] => 3 [authorName] => Author 3 ) [3] => Array ( [bookId] => 3 [bookName] => Book 3 [authorId] => 4 [authorName] => Author 4 ) ) Array ( [1] => Array ( [bookId] => 1 [bookName] => Book 1 [authorName] => Array ( [0] => Author 1 [1] => Author 2 ) ) [2] => Array ( [bookId] => 2 [bookName] => Book 2 [authorName] => Array ( [2] => Author 3 ) ) [3] => Array ( [bookId] => 3 [bookName] => Book 3 [authorName] => Array ( [3] => Author 4 ) ) )

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241.76 ms | 405 KiB | 339 Q