PHP CodeIgniter DB get受影响行id的数组

只需在更新前获取目标行:-

$result=$this->db->select('id')
     ->from('table_name')
     ->where_not_in('id', $notEditableIds)
     ->where($key, $oldValue)
     ->or_where($key, NULL)->result_array();
$this->db->where_not_in('id', $notEditableIds)
         ->where($key, $oldValue)
         ->or_where($key, NULL)
         ->update('fields', array($key => $value));
if($this->db->affected_rows()){
   return $result;
}
 else{
 return []; 
}