Join does not work in Hbase

select student.onecf['name'] name from student inner join voter on (student.onecf['name'] = voter.onecf['name']);
Query failed: Failure while running fragment. Failure finding function that runtime code generation expected.  Signature: compare_to( VARBINARY:OPTIONALINT:OPTIONAL,  ) returns INT:REQUIRED [0ffd82e9-43ac-4a29-934f-b72fa76ddb78]