Hive Explain Plan

[#1]

I am trying to understand how the EXPLAIN PLAN statement generates the plan for a given query.

I have checked out the code from apache/github.

I am unable to find any document/link that atleast points me where do I start looking in the code or atleast what steps does the explain plan perform to arrive at the query plan.

Any pointers will be helpful.

[#2 · Accepted solution]

Hi @Ramesh Prasad,

You may want to start looking at Apache Calcite. Calcite is the primary CBO behind Hive execution.