Hello All,

I would like to know if anyone of you faced this issue with HIVE CBO and
also would like to get some directions as to how to go about resolving it.

We are using Hive 1.2.1. When we were evaluating the benefits of Cost based
Optimization(CBO), we stumbled upon this.

1) Queries which had single level join when run always had this thing in
the log. "Not invoking CBO because the statement has too few joins".  Can
anyone confirm this. Join optimization happens only when there are more
than 1 join? Is there a way around this.

2) Also, Can CBO automatically do a Map join(without Hive's set
auto-convert statement) if assesses that one of the table involved is small
and could be broadcasted?

Thanks in advance!!

Regards,
Venkatesh Selvaraj

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