if (empty($this->sql_from)) {
            // construct default SELECT and FROM clauses using parent relations
            $this->sql_from    = null;
            $this->sql_groupby = null;
            $this->sql_having  = null;
            $this->sql_from    = $this->_sqlForeignJoin($this->sql_select, $this->sql_from, $this->parent_relations);

	        // add code to obtain grade amount
	        $this->sql_select .= ", crf_type.crf_type_id";
	        $this->sql_from   .= " LEFT JOIN crf_type ON branch.crf_type_id=crf_type.crf_type_id";
    	} // if