protected function _hasJoin_sql($key, $table, $cond, &$filter, &$options) {
		$relConf = $this->fieldConf[$key]['belongs-to-one'];
		$relModel = is_array($relConf)?$relConf[0]:$relConf;
		$rel = $this->getRelInstance($relModel,null,$key);
		$fkey = is_array($this->fieldConf[$key]['belongs-to-one']) ?
			$this->fieldConf[$key]['belongs-to-one'][1] : $rel->primary;
		$alias = $table.'__'.$key;
		$query = $this->_sql_left_join($key,$this->table,$fkey,[$table,$alias]);
		$this->_sql_mergeRelCondition($cond,$alias,$filter,$options);
		return $query;
	}