@Override
  public void setFinal(Column finalResult) {
    if (finalResult.isNull(0)) {
      return;
    }
    initResult = true;
    updateX(finalResult, 0);
  }
max(x,y) returns the value of x associated with the maximum value of y over all input values.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/aggregation/MaxMinByBaseAccumulator.java