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<?php $rows = [ ['3', '2022-01-03'], ['5,3', '2022-01-15'], ['4', '2022-01-27'], ['5', '2022-02-01'], ['7', '2022-02-09'], ['3,2', '2022-01-16'], ]; $counts = []; foreach($rows as $row){ $ids = explode(',', $row[0]); $month = date('m', strtotime($row[1])); foreach($ids as $id){ if(!array_key_exists($id, $counts)){ $counts[$id] = []; } if(!array_key_exists($month, $counts[$id])){ $counts[$id][$month] = 0; } $counts[$id][$month]++; } } var_dump($counts);
Output for 7.4.0 - 7.4.33, 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(5) { [3]=> array(1) { ["01"]=> int(3) } [5]=> array(2) { ["01"]=> int(1) ["02"]=> int(1) } [4]=> array(1) { ["01"]=> int(1) } [7]=> array(1) { ["02"]=> int(1) } [2]=> array(1) { ["01"]=> int(1) } }
preferences:
96.3 ms | 1297 KiB | 4 Q