public boolean isCrossJoin() {
    return !asofCriteria.isPresent()
        && criteria.isEmpty()
        && !filter.isPresent()
        && joinType == INNER;
  }
@return a new JoinNode with the flipped attributes
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/relational/planner/node/JoinNode.java