Hi All, I am a new bee to Cassandra and trying to understand how secondary indexes work. I have been going over the discussion on https://issues.apache.org/jira/browse/CASSANDRA-749 about local secondary indexes. And interesting question on http://www.mail-archive.com/user@cassandra.apache.org/msg16966.html. The discussion seems to assume that most common uses cases are ones with range queries. Is this right?
I am trying to understand the low cardinality reasoning and how the read gets executed. I have following questions, hoping i can explain my question well :) 1. When a write request is received, it is written to the base CF and secondary index to secondary (hidden) CF. If this right, will the secondary index be written local the node or will it follow RP/OPP to write to nodes. 2. When a coordinator receives a read request with say predicate x=y where column x is the secondary index, how does the coordinator query relevant node(s)? How does it avoid sending it to all nodes if it is locally indexed? If there is any article/blog that can help understand this better, please let me know. Thanks again in advance. VR