Will secondary index create another copy of data in cassandra?

Question

I have been through this document but here it doesn't say if the data is made a copy of because of secondary index or its just having links to other data ?

Answer 1

Secondary indexes create a copy of the index table (just index data, not the whole table of data) on each node. Datastax has a very good write up on how secondary indexes work and when/when not to use them.

https://docs.datastax.com/en/cql/3.3/cql/cql_using/useSecondaryIndex.html