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<?php $attendances = json_decode('[ { "id": 4, "student_id": "18", "admission_no": "S18/2023", "class_id": "1", "session": "2022/2023", "marked": "present", "marked_date": "2023-05-15", "created_at": "2023-05-15 09:22:28" }, { "id": 2, "student_id": "18", "admission_no": "S18/2023", "class_id": "1", "session": "2022/2023", "marked": "absent", "marked_date": "2023-05-12", "created_at": "2023-05-12 14:06:55" } ]', true); foreach($attendances as $attendance) { $result[(int)explode('-', $attendance['marked_date'])[2]] = $attendance; } print_r($result);
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Array ( [15] => Array ( [id] => 4 [student_id] => 18 [admission_no] => S18/2023 [class_id] => 1 [session] => 2022/2023 [marked] => present [marked_date] => 2023-05-15 [created_at] => 2023-05-15 09:22:28 ) [12] => Array ( [id] => 2 [student_id] => 18 [admission_no] => S18/2023 [class_id] => 1 [session] => 2022/2023 [marked] => absent [marked_date] => 2023-05-12 [created_at] => 2023-05-12 14:06:55 ) )

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