SQL_Model::tryLoadBy PHP Method

    public function tryLoadBy($field, $cond = UNDEFINED, $value = UNDEFINED)
    {
        $q = $this->dsql;
        $this->dsql = $this->dsql();
        $this->addCondition($field, $cond, $value);
        $this->tryLoadAny();
        $this->dsql = $q;
        return $this;
    }