Technologysolr

See setupZookeeperHadoopHbaseTomcatSolrNutch for an advanced setup.

• HathiTrust Solr Benchmarking
• Comparison of accuracy and perforce of language detect tools

Documentation

Starting from release 4.4.0 there will be a Solr Reference Guide for every minor release. We are currently using 4.3.1. But it should be helpful anyway.

• Apache Solr 4.4.0 Reference Guide

Query Syntax

Debug information can be appended to a query by adding &debugQuery=on to the request.

Solr can parse Queries with multiple QueryParsers:

• Dismax Query Parser: Features a query syntax similar to the one Google uses. Is relatively simple and highly fault tolerant. It is designed, to make it possible to forward user queries directly to Solr.
• Standard Query Parser: A query syntax enabling more complicated and precise queries. However user input would have to be escaped/parsed heavily to be forwarded to Solr.

Currently I favor Dismax Query Parser because it's probably easier to implement. An implementation of Standard Query Parse would most likely result in trying to emulate Dismax' syntax, but not reaching its quality.

Open Questions

Solr supports a feature called MoreLikeThis which can return all documents similiar to another one. This is different from fuzzy searching. Note: I don't know where we would use this quire yet, but it seems interesting.