unresolved operator union in Spark 1.6

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 s

Unresolved operator Union in Spark 1.6

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