code: private function getForcedCustomersIds()
      {
          $mlmIds = array_keys($this->QUALIFIED_CUSTOMERS);
          $where = '';
          foreach ($mlmIds as $one) {
              /* skip first iteration */
              if (strlen($where) > 0) {
                  $where .= ' OR ';
              }
              $quoted = $this->conn->quote($one);
              $where .= Customer::A_MLM_ID . "=\"$quoted\"";
          }
          $cols = [Customer::A_CUSTOMER_REF, Customer::A_MLM_ID];
          $result = $this->daoGeneric->getEntities(Customer::ENTITY_NAME, $cols, $where);
          return $result;
      }
docs: IDs for customers with forced qualification.
  
  @return array [[Customer::A_CUSTOMER_ID=>..., Customer::A_MLM_ID=>...], ...]