Scenario: UNION result handling

Previous Behavior: queries in which union operator was used may have created an invalid output type.for example, the column type is ambigous in the following query:

select cast(1 as int) union select cast(1 as string)

Selecting the inappropriate type may cause the value to be changed to NULL.

New Behavior: The types are checked prior to execution; and the ambigous cases are rejected;

FAILED: SemanticException Schema of both sides of union should match: Column _c0 is of type int on first table and type string on second table. Cannot tell the position of null AST. (state=42000,code=40000)

The query should be clarified with explicit casts.

Component Affected: Ranger resource based policies

Previous Behavior: HDFS trash does not descend into child directories to check if a user has permission to delete files.

New Behavior: Adds a permission check for moving files to Trash. HDFS will now check permissions on child directories before moving a directory into trash.

Scenario:Additional ranger hive policies required for INSERT OVERWRITE

Previous behavior: Hive INSERT OVERWRITE queries succeed as usual.

New behavior: Hive INSERT OVERWRITE queries are unexpectedly failing after upgrading to HDP-2.6.x with the error:

Error while compiling statement: FAILED: HiveAccessControlException Permission denied: user jdoe does not have WRITE privilege on /tmp/*(state=42000,code=40000)

As of HDP-2.6.0, Hive INSERT OVERWRITE queries require a Ranger URI policy to allow write operations, even if the user has write privilege granted through HDFS policy.

Workaround/Expected Customer Action: