protected final Map<PartialPath, ViewExpression> convertTargetAndSourceListsToMap(
      List<PartialPath> paths, List<ViewExpression> expressions) {
    if (paths.size() != expressions.size()) {
      return null;
    }
    Map<PartialPath, ViewExpression> result = new HashMap<>();
    for (int i = 0; i < paths.size(); i++) {
      result.put(paths.get(i), expressions.get(i));
    }
    return result;
  }
This variable will be set in function splitByPartition() according to analysis. And it will be
set when creating new split nodes.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/planner/plan/node/metadata/write/view/CreateLogicalViewNode.java