code: private function getCalcId($dsBegin, $treeType)
      {
          $codeRegular = $codeForecast = '';
          if ($treeType == OptionTreeType::VAL_PLAIN) {
              $codeRegular = Cfg::CODE_TYPE_CALC_PV_WRITE_OFF;
              $codeForecast = Cfg::CODE_TYPE_CALC_FORECAST_PLAIN;
          } elseif ($treeType == OptionTreeType::VAL_COMPRESS) {
              $codeRegular = Cfg::CODE_TYPE_CALC_COMPRESS_PHASE1;
              $codeForecast = Cfg::CODE_TYPE_CALC_FORECAST_PHASE1;
          }
          $query = $this->qGetId->build();
          $conn = $query->getConnection();
          $bind = [
              QGetId::BND_DS_BEGIN => $dsBegin,
              QGetId::BND_TYPE_CODE_REGULAR => $codeRegular,
              QGetId::BND_TYPE_CODE_FORECAST => $codeForecast
          ];
          $result = $conn->fetchOne($query, $bind);
          return $result;
      }
docs: Get calculation ID for given period & tree type.
  
  @param string $dsBegin YYYYMMDD period's begin datestamp
  @param string $treeType [compressed|plain]
  @return int