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<?php $array = [ [ 'avgvalue' => 0, 'timestamp' => '2011-02-04T11:00:00.000Z', ], [ 'avgvalue' => 268.3, 'timestamp' => '2011-02-04T12:00:00.000Z' ], ]; $result = []; foreach ($array as $row) { $result[substr($row['timestamp'], 0, 10)][] = $row; } var_export($result);
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.31, 8.3.0 - 8.3.31, 8.4.1 - 8.4.22, 8.5.0 - 8.5.7
array ( '2011-02-04' => array ( 0 => array ( 'avgvalue' => 0, 'timestamp' => '2011-02-04T11:00:00.000Z', ), 1 => array ( 'avgvalue' => 268.3, 'timestamp' => '2011-02-04T12:00:00.000Z', ), ), )
preferences:
100.26 ms | 1434 KiB | 4 Q