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<?php $array = [ 'a' => [ 'name' => "Name 1", 'age' => "99", 'add' => "" ], 'b' => [ 'name' => "Name 2", 'age' => "99", 'add' => "Add2" ], 'c' => [ 'name' => "Name 3", 'age' => "99", 'add' => "Add3" ], 'd' => [ 'name' => "", 'age' => "", 'add' => "Add4" ] ]; var_export( array_filter( array_map( fn($row) => array_keys( array_filter( $row, fn($v) => !strlen($v) ) ), $array ) ) );

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