Hive运行select job,count(*) from users group by job；没有结果并发出警告

Hive运行select job,count(*) from users group by job；没有结果并发出警告

发出的警告：Hive-on-MR is deprecated in Hive 2 and may not be available in the future versions. Consider using a different execution engine (i.e. spark, tez) or using Hive 1.X releases.

原因：yarn没有启动，或者已经停止运作

解决方法：先关掉所有的进程，重新运行hdfs和yarn（start-all.sh或者start-dfs.sh    start-yarn.sh）