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Apache Lucene BlendedInfixSuggester : How It Works, Bugs And Improvements

The Apache Lucene/Solr suggesters are important to Sease : we explored the topic in the past[1] and we strongly believe the autocomplete feature to be vital for a lot of search applications. This blog post explores in details the current status of the Lucene BlendedInfixSuggester, some bugs of the most recent version ( with the … Continue reading Apache Lucene BlendedInfixSuggester : How It Works, Bugs And Improvements

SolrCloud exceptions with Apache Zookeeper

At the time we speak ( Solr 7.3.1 ) SolrCloud is a reliable and stable distributed architecture for Apache Solr. But it is not perfect and failures happen. Apache Zookeeper[1] is the system responsible of managing the communications across the SolrCloud cluster. It contains the shared collections configurations and it has the view of the … Continue reading SolrCloud exceptions with Apache Zookeeper

Apache Solr: orchestrating Known item and Full-text search

Scenario You’re working as a search engineer for XYZ Ltd, a company which sells electric components. XYZ provided you the application logs of the last six months, and some business requirements. Two kinds of customers, two kinds of requirements, two kinds of search The log analysis shows that XYZ has mainly two kinds of customers: … Continue reading Apache Solr: orchestrating Known item and Full-text search

SolrCloud Leader Election Failing

At the time we speak ( Solr 7.3.0 ) SolrCloud is a reliable and stable distributed architecture for Apache Solr. But it is not perfect and failures happen. This lightening blog post will present some practical tips to follow when a specific shard of a collection is down with no leader and the situation is … Continue reading SolrCloud Leader Election Failing

Give the height the right weight: quantities detection in Apache Solr

Quantity detection? What is a quantity? And why do we need to detect it? A quantity, as described by Martin Fowler in his "Analysis Patterns" [1] is defined as a pair which combines an amount and unit (such as 30 litres, 0.25 cl, or 140 cm). In search-based applications, there are many cases where you may … Continue reading Give the height the right weight: quantities detection in Apache Solr

ECIR 2018 Experience

This blog is a quick summary of my (subjective) experience at ECIR 2018 : the 40th European Conference on Information Retrieval, hosted in Grenoble (France) from 26/03/2018 to 29/03/2018. Deep Learning and Explicability Eight long papers accepted were about Deep Learning. The topics "Neural Network" and "Word Embedding" were the most occurring in the accepted … Continue reading ECIR 2018 Experience

Apache Solr: Chaining SearchHandler instances: the CompositeRequestHandler

What are "Invisible Queries"? This is an extract of an article [1] on Lucidworks.com, by Grant Ingersoll, talking about invisible queries: "It is often necessary in many applications to execute more than one query for any given user query.  For instance, in applications that require very high precision (only good results, forgoing marginal results), the … Continue reading Apache Solr: Chaining SearchHandler instances: the CompositeRequestHandler

Distributed Search Tips for Apache Solr

Distributed search is the foundation for Apache Solr Scalability : It's possible to distributed search across different Apache Solr nodes of the same collection ( both in a  legacy[1] or SolrCloud[2] architecture), but it is also possible to distribute search across different collections in a SolrCloud cluster. Aggregating results from different collections may be useful … Continue reading Distributed Search Tips for Apache Solr

Solr Is Learning To Rank Better – Part 4 – Solr Integration

Last Stage Of The Journey This blog post is about the Apache Solr Learning To Rank ( LTR ) integration. We modelled our dataset, we collected the data and refined it in Part 1 . Trained the model in Part 2 . Analysed and evaluate the model and training set in Part 3 . We … Continue reading Solr Is Learning To Rank Better – Part 4 – Solr Integration

Solr Is Learning To Rank Better – Part 3 – Ltr tools

Apache Solr Learning to Rank - Things Get Serious This blog post is about the Apache Solr Learning to Rank Tools : a set of tools to ease the utilisation of the Apache Solr Learning To Rank integration. The model has been trained in Part 2, we are ready to deploy it to Solr, but … Continue reading Solr Is Learning To Rank Better – Part 3 – Ltr tools