One of the additions to Solr that we didn’t talk about yet is the new field type called the RankField and the Rank Query Parser that can leverage it. Together they can be used to introduce scoring based on the content of the document in an optimized way. Let’s have a quick look at what the mentioned pair gives us.
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SolrCloud and query execution control
With the release of Solr 7.0 and introduction of new replica types, in addition to the defa?ult NRT type the question appeared – can we control the queries and where they are executed? Can we tell Solr to execute the queries only on the PULL replicas or give TLOG replicas a priority? Let’s check that out.
Read moreSolr 6.0 and graph traversal support
One of the new features that are present in the recently released Solr 6.0 is the graph traversal query that allows us to work with graphs. Having a root set and relations between documents (like parent identifier of the document) we can use a single query to get multiple levels of joins in the same request. Let’s look at this new feature working both in old fashioned Solr master – slave as well as in SolrCloud.
Switch Query Parser – quick look
The number of different query parsers in Solr was always an amusement for me. Can someone here say how many of them are currently available and say what are those? Anyway, in this entry we won’t be talking about all the query parsers available in Solr, but we will take a quick look at one of them – the SwitchQueryParser introduced in Solr 4.2.
Do I have to look for maxBooleanClauses when using filters ?
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.
Quick look: frange
In Solr 1.4 there were a new type of queries presented the frange queries. This new type of queries let you search for a range of values. According to the Solr developers this queries should be much faster from normal range queries. I thought that I should make a simple test to see how much faster, the new range queries can be expected to be.
Optimization – query result window size
Hereby I would like to start a small series of articles describing the elements of the optimization of Solr instances. At first glance I decided to describe the parameter that specifies the data fetch window size – the query result window size. Hopefully, this article will explain how to use this parameter, how to modify and adapt it to your needs.
The scope of Solr faceting
Faceting is one of the ways to categorize the content found in the process of information retrieval. In case of Solr this is the division of set of documents on the basis of certain criteria: content of individual fields, queries or on the basis of compartments or dates. In today’s entry I will try to some scope on the possibility of using the faceting mechanism, both currently available in Solr 1.4.1, as well as what will be available in the future.
6 deadly sins in the context of query
In my work related to Lucene and Solr I have seen various queries. While in the case of Lucene, developer usually knows what he/she wants to achieve and use more or less optimal solution, but when it comes to Solr it is not always like this. Solr is a product which could theoretically be used by everyone, both the person who knows Java, one that does not have a broad and specialized technical knowledge, as well as programmer. Precisely because of that Solr is a product which is easy to run and use it, at least when it comes to simple functionalities. I suppose, that is why not many people are worried about reading Solr wiki or at least review the mailing list. As a result, sooner or later people tend to make mistakes. Those errors arise from various shortcomings – lack of knowledge about Solr, lack of skills, lack of experience or simply a lack of time and tight deadlines. Today I would like to show some major mistakes when submitting queries to Solr and how to avoid those mistakes.
Solr and PhraseQuery – phrase bonus in query stage
In the majority of system implementations I dealt with, sooner or later, there was a problem – search results tunning. One of the simplest ways to improve the search results quality was phrase boosting. Having the three most popular query parsers in Solr and the variety of parameters to control them I though it will be a good idea to check how they behave and how they affect performance.