Why are document stores like Lucene / Solr not included in NoSQL conversations?

Question

All of us have come across the recent hype of no-SQL solutions lately. MongoDB, CouchDB, BigTable, Cassandra, and others have been listed as no-SQL options. Here\'s an examp

Answer 1

The main differences between a no sql and solr in operational wise are the following in my opinion.

1. Solr requires an intermediate data store (database or XML files) whereas nosql itself a straight data store.
2. You cannot do a constant writes to solr (solr 4.0 seems to bring that support) and you can only index at the max of every 2 mins and 200 records (which is very slow for high throughput writes and you are forced for an intermediate storage).
3. You are require to change / define the schema when you alter what is stored in document. NoSQL has no such definitions.
4. Solr indexes has performance implication when its index size grows whereas NoSQL is optimized for it (or claims to be :) )
5. Solr has underlying lucene search algorithms bundled but in NoSQL you need to build them, This applies to the magnificent faceted search or blazing fast document search provided by solr.