hive group by 语法增强

需要在hive-site.xml配置文件中添加如下内容才能使用group by 语法增强，group by除了可以跟column alias，也可以跟column position，比如：select f1(col1), f2(col2), f3(col3), count(1) group by f1(col1), f2(col2), f3(col3);可以写成select f1(col1), f2(col2), f3(col3), count(1) group by 1, 2, 3;

<property>
  <name>hive.groupby.orderby.position.alias</name>
  <value>true</value>
  <description>Whether to enable using Column Position Alias in Group By or Order By</description>
</property>