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<?php $rrDatas = [ [], [ "asset" => 1, "person" => 1, ], [ "asset" => 2, ], [ "test" => 1, "person" => 1, ], [ "person" => 1, "banana" => "hello", "person" => 4, ], ]; $output = []; // Prepare empty output foreach($rrDatas as $inner){ foreach($inner as $key => $value){ $output[$key][] = $value; } } echo json_encode($output); // {"asset":[1,2],"person":[1]}
Output for 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
{"asset":[1,2],"person":[1,1,4],"test":[1],"banana":["hello"]}

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130.3 ms | 407 KiB | 5 Q