original_string: protected function _columnNames()
      {
          $columns = [];
          foreach ($this->_columns as $col) {
              if (is_string($col)) {
                  $col = trim($col, '`[]"');
              }
              $columns[] = $col;
          }
  
          return $columns;
      }
code: protected function _columnNames()
      {
          $columns = [];
          foreach ($this->_columns as $col) {
              if (is_string($col)) {
                  $col = trim($col, '`[]"');
              }
              $columns[] = $col;
          }
  
          return $columns;
      }
code_tokens: protected function _columnNames ( ) { $ columns = [ ] ; foreach ( $ this -> _columns as $ col ) { if ( is_string ( $ col ) ) { $ col = trim ( $ col , '`[]"' ) ; } $ columns [ ] = $ col ; } return $ columns ; }
docstring: Get the bare column names.
  
  Because column names could be identifier quoted, we
  need to strip the identifiers off of the columns.
  
  @return array
docstring_tokens: Get the bare column names .