public void setNanStringInferType(TSDataType nanStringInferType) {
    if (nanStringInferType != TSDataType.DOUBLE
        && nanStringInferType != TSDataType.FLOAT
        && nanStringInferType != TSDataType.TEXT) {
      logger.warn(
          "Config Property nan_string_infer_type can only be FLOAT, DOUBLE or TEXT but is {}",
          nanStringInferType);
      return;
    }
    this.nanStringInferType = nanStringInferType;
  }
if the folders are relative paths, add IOTDB_DATA_HOME as the path prefix
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBConfig.java