About the data structure of partition index

[Hiroyuki Yamada <mo...@gmail.com>]

Hi,

I am wondering how many primary keys are stored in one partition index.

As the following documents say,

<https://docs.datastax.com/en/glossary/doc/glossary/gloss_primary_index.html>
<http://docs.datastax.com/en/cassandra/2.2/cassandra/dml/dmlAboutReads.html>

I understand that each partition index has a list of primary keys and
the start position of compression offset map,
So, I assume the logical data structure of a partition index would be
like the following:

| [pkey1-pkeyN] | offset-to compression offset map |
(indexed by the first column to retrieve by a partition key)

I am wondering if it is a correct understanding and
how many primary keys are stored in the first column.

If it is not correct, would anyone give me the correct logical data structure ?

Thanks,
Hiro