code: function offsetGet($key){
          if($this->single && !isset($this->data)){
              $clone = clone $this;
              if(is_array($key)){
                  $clone->where($key)->limit(1);
              }else{
                  $clone->where($this->primary, $key);
              }
              $return = $clone->fetch();
              if($return){
                  return $return;
              }
          }else{
              $this->execute();
              if(is_array($key)){
                  foreach($this->data as $row){
                      foreach($key as $k => $v){
                          if((isset($v) && $row[$k] !== null ? $row[$k] != $v : $row[$k] !== $v)){
                              continue 2;
                          }
                      }
                      return $row;
                  }
              }elseif(isset($this->data[$key])){
                  return $this->data[$key];
              }
          }
          return NULL;
      }
docs: Get specified row
  
  @param string $key row ID or array for where conditions
  
  @return NotORM_Row or null if there is no such row