private static boolean isPartitionedTable(Table tableObj) {
    List<FieldSchema> partKeys = tableObj.getPartitionKeys();
    if (partKeys != null && partKeys.size() > 0) {
      return true;
    }
    return false;
  }
It's assumed everywhere that original data files are named according to
{@link #ORIGINAL_PATTERN} or{@link #ORIGINAL_PATTERN_COPY}
This checks that when transaction=true is set and throws if it finds any files that don't
follow convention.
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/TransactionalValidationListener.java