You can upgrade your Spark to version 2.x.
At 2019-08-20 19:16:50, "马阳阳" <ma_yang_y...@163.com> wrote: Hi all, We encountered the following problem when using Spark 1.6. The following SQL: ``` SELECT a,b,c FROM A UNION ALL SELECT a,b,c FROM B ``` If A and B are two views created with SQLContext.registerDataFrameAsTable(), Spark will fail with “unresolved operator Union”. But if A and B are saved to two hive temp tables, respectively, Spark can run the sql successfully. The sql is run with HiveContext.sql((). Any help is appreciated.