original_string: public function indexBy($field)
      {
          $this->data = $this->executeIndexBy($this->data, $field);
          $this->indexBy = $field;
          return $this;
      }
code: public function indexBy($field)
      {
          $this->data = $this->executeIndexBy($this->data, $field);
          $this->indexBy = $field;
          return $this;
      }
code_tokens: public function indexBy ( $ field ) { $ this -> data = $ this -> executeIndexBy ( $ this -> data , $ field ) ; $ this -> indexBy = $ field ; return $ this ; }
docstring: Specifies a field to be the key of the fetched array
  
  @param string $field
  @return $this
docstring_tokens: Specifies a field to be the key of the fetched array