public TSStatus addRegionLocation(AddRegionLocationPlan req) {
    databasePartitionTables.values().stream()
        .filter(
            databasePartitionTable -> databasePartitionTable.containRegionGroup(req.getRegionId()))
        .forEach(
            databasePartitionTable ->
                databasePartitionTable.addRegionNewLocation(
                    req.getRegionId(), req.getNewLocation()));
    return new TSStatus(TSStatusCode.SUCCESS_STATUS.getStatusCode());
  }
The region has expanded to a new DataNode, now update the databasePartitionTable.
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/persistence/partition/PartitionInfo.java