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<?php $array1 = array ( 'a' => array ( 'banner_id' => '4', 'viewsCount' => '33', 'date' => '2015-06-19' ) ); $array2 = array ( 'a' => array ( 'banner_id' => '4', 'clicksCount' => '5', 'date' => '2015-06-19' ) ); print_r (array_merge_recursive($array1, $array2));
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 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 - 8.3.6
Array ( [a] => Array ( [banner_id] => Array ( [0] => 4 [1] => 4 ) [viewsCount] => 33 [date] => Array ( [0] => 2015-06-19 [1] => 2015-06-19 ) [clicksCount] => 5 ) )

preferences:
296.86 ms | 406 KiB | 354 Q