In the previous entry “Developing Your Own Solr Filter” we’ve shown how to implement a simple filter and how to use it in Apache Solr. Recently, one of our readers asked if we can extend the topic and show how to write more than a single token into the token stream. We decided to go for it and extend the previous blog entry about filter implementation.
Sometimes Lucene and Solr out of the box functionality is not enough. When such time comes, we need to extend what Lucene and Solr gives us and create our own plugin. In todays post I’ll try to show how to develop a custom filter and use it in Solr.
One of the configuration variables we can find in the solrconfig.xml file is maxBooleanClauses, which specifies the maximum number of boolean clauses that can be combined in a single query. The question is, do I have to worry about it when using filters in Solr ? Let’s try to answer that question without getting into Lucene and Solr source code.
Continuing the overview of the filters included in Solr today we look at the PatternReplaceCharFilter.
As you might guess the task of the filter is to change the matching input stream parts that match the given regular expression.
This time I decided to look at one of the unusual filters available in the standard distribution of Solr. The first one in my hands is a filter called KeepWordFilter.
Today’s entry is dedicated to one type of cache in the Solr – filter cache. I will try to explain what it does, how to configure it and how to use it in an efficient way.
During my everyday work, I have seen many repeated queries, to Solr, with only one filter difference. When I asked why – I got anserws that it was necessary to get the faceting results for various filters. If you are using Solr version 1.4 or later, my suggestion is to use local params – what is it and how to use – this post will attempt to answer both questions.
One of the configuration files that describe each implementation Solr is schema.xml file. It describes one of the most important things of the implementation – the structure of the data index. The information contained in this file allow you to control how Solr behaves when indexing the data, or when making queries. Schema.xml is not only the very structure of the index, is also detailed information about data types that have a large influence on the behavior Solr, and usually are treated with neglect. This entry will try to bring some insight about schema.xml.