I am seeing some odd behavior with indexes and want some clarification on how they are used.

When I create an table in phoenix on top of an existing Hbase table, and then create an index on this table, I can see the index get built and populated properly, however no queries show that they are using this index when I run an explain on the query. 

However, if I create an seperete table in Phoenix and do an upsert from my hbase table into the new table that I created, and create the same index as on the previous table. Then my queries show that they would use the index when running them through the explain plan. 

Are we not able to create or use an index on a table we create over an exiting Hbase table, or am I doing something wrong?

Thanks in advance for any help.
Justin