docs: public final int setPartitionColumnName(String partitionColumnName) {
          if (partitionColumnName == null || partitionColumnName.trim().isEmpty()) {
              return PARTITION_ID_INDEX;
          }
          int idx = -1;
          for (String name : m_source.columnNames) {
              if (name.equalsIgnoreCase(partitionColumnName)) {
                  idx = m_source.columnNames.indexOf(name);
                  break;
              }
          }
          if (idx == -1) {
              m_partitionColumnIndex = PARTITION_ID_INDEX;
              m_logger.error("Export configuration error: specified " + m_source.tableName + "." + partitionColumnName
                      + " does not exist. A default partition or routing key will be used.");
          } else {
              m_partitionColumnIndex = idx;
          }
          return m_partitionColumnIndex;
      }