@Override
  public Pattern<OffsetNode> getPattern() {
    return PATTERN;
  }
<b>Optimization phase:</b> Distributed plan planning.

<p>The OFFSET can be eliminated when the following conditions are met:
<li>Its child is DeviceTableScan, which means there OFFSET is effect on only one region
<li>The query expressions are all scalar expression.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/relational/planner/iterative/rule/PushDownOffsetIntoTableScan.java