Rafal Kuc is a team leader and software developer. Right now he is a software architect and Solr and Lucene specialist. Mainly focused on Java, but open on every tool and programming language that will make the achievement of his goal easier and faster. Rafal is also one of the founders of solr.pl site where he tries to share his knowledge and help people with their problems. Rafał is a DZone MVB and is not an employee of DZone and has posted 75 posts at DZone. You can read more from them at their website. View Full User Profile

Explain.solr.pl beta version available

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We are pleased to announce, that http://explain.solr.pl is now available for users. Please remember that this is a beta version and will be further developed. If you want to know more details please read the following blog post.


Currently explain.solr.pl can analyze the queries from the 3.x version of Solr and it’s getting ready to handle 4.0 version of Solr.

Explain visualization

In the current version of explain.solr.pl visualizes score values of the given documents.

In order to add a new 'explain' visualization you need to run your query with an additional debugQuery=on parameter and then paste the result returned by Solr to explain.solr.pl (if you will use web browser to get the results please remember to paste the page source). After hitting the “Create explain” button your explain visualization will be created and you will be taken to that visualization web page. Currently explain.solr.pl supports only results in XML format, so if you use another format (like json) please ommit the wt parameter or set it to wt=xml.

It is also possible to verify hits for any document, even one that was not found in the search results (given to Solr with the use of explainOther parameter). It can be useful to check why the given document wasn’t included in the result list.

Available information

After creating the new explain visualization you have a series of information available. Information about the query is shown ones for the whole explain, while the rest of the information is shown for each document.

Information about query

In this part of explain.solr.pl you can see:

  1. Unique identifier of your explain visualization.
  2. Information about debugOther parameter not being used.
  3. The actual query.
  4. Information about explain visualization being available to public.

Fields and values

In this part of the explain.solr.pl you can see information about fields and theirs values that were available in the search results.

Visualization of elements influencing total score value

The following information is visible in this part of the explain.solr.pl:

  1. Percentage influence of each value on the global score value of the document.
  2. Pie chart visualizing the data visible in the left column.

Getting back to once visualized explain

If you wish to get back to your once visualised explain please to the following URL address: http://explain.solr.pl/explains/EXPLAIN_ID, where EXPLAIN_ID is the unique identifier of your explain. If you don’t remember unique identifier of your visualized explain, you can find it out in the “history” page.

Hiding your explain

If you don’t want your explain information to be available to public, please uncheck the “I want this explain to be visible on history page” checkbox during explain creation. Please remember that in order to get back to private explain you will need to remember its unique identifier.

Issues raising

To raise a new issue You found in explain.solr.pl, please create a new issue on https://github.com/solrpl/explain or send a mail to explain(at)solr(dot)pl.


We also have a request to the community. If you have some notes, if you encounter an error or would like some additional functionality please write an mail to explain(at)solr(dot)pl. This will allow us to better understand Your needs and will make explain.solr.pl better suite Your needs.

Something at the end

At the very end we would like to show you how the process of developing http://explain.solr.pl looks like. We used a tool called gsource :)

Published at DZone with permission of Rafał Kuć, author and DZone MVB. (source)

(Note: Opinions expressed in this article and its replies are the opinions of their respective authors and not those of DZone, Inc.)