Sample and Aggregate Rewritten Queries

[Saylboat]

I'm using FLEX to create a simple demo of differentially private queries with a real hive database running the rewritten queries. The problem I'm having is that the rewritten sample and aggregate queries do not execute on my hive database. Hive does not like the underscores in front of variables and the use of UNION in the rewritten query while parsing. Are there any databases that are confirmed to work with all rewritten queries? Perhaps I'm using a newer version of hive that's incompatible with this build of FLEX? Any help or pointers would be nice.