Adjusting your website's search result ordering and matching (often referred to as tweaking results) can be as complicated a topic as you want to make it. To help you with this process, the Apache Solr Search Integration module provides several hooks and user interface options to tweak your website's results. The combination of hooks and settings that works for you depends on your architecture, your customers' behavior, and your real-world user testing.
Use these methods to get the best possible results, make small changes, and then test and get feedback. Evaluate what the most natural results would be for searches, and then make modifications.
Here are some of the available options:
- Use biasing options to tweak result ordering
Use the biasing options in the Drupal user interface either to tweak result ordering by newness or by entity type, or to give more importance to matches in taxonomy terms, titles, or other fields.
To view your website's biasing options, sign in as an administrator, go to Configuration > Apache Solr Search > Settings, and then click Bias next to the search environment that you want to edit. You can also read the Acquia Search documentation on Using bias to tune search results. For example, an easy way to bubble up items on search results is if those nodes are marked as sticky at top of lists. You will also need to work with your editors to understand when and how to set this flag.
- Use modules to help boost matching terms
By using modules such as the Apachesolr Term Proximity module, you can provide better results when users are searching for phrases. For example, a search for
parking permitswill boost items that have the exact phrase in their contents above items that have the words shown separately.
- Create custom code that implements hooks
Using hooks like
hook_apachesolr_query_alter()can change the queries sent to Solr as those queries are being made. Hooks can also introduce complex boosting or ordering commands onto the Solr query.
- Create hard overrides of the searching behavior
You can create these overrides by editing the following text files in your Solr configuration:
synonyms.txt- Allows you to swap words
For example, a search for
garagecan only match
parking, or searches for both
parkingcan be equivalent and match either
protwords.txt- Allows you to force Solr to always take words as they are and not cut them down to their root
This prevents Solr from stemming words. Normally, a search for
parker, but adding
protwords.txtensures that searches will only match the exact term:
elevate.xml- Allows you to force certain items to show up among the first results for a specific search
For example, modifying this file allows you to always display
parkingas the first result when website visitors search for phrases like
where to park. The Solr best bets module can help you construct this file. Once you have created and tested a version of this file, contact Acquia Support to begin its placement on your server.
stopwords.txt- Allows you to tell Solr which words are not meaningful and should be dropped from queries and indexing
For indexing items that are not nodes, the Apache Solr Not a Node module can be useful.
Monitoring website visitors' search experiences
You can use tools like Google Analytics to track searches and see what your visitors are looking for. It might also be worth tracking low-result and no-result searches, which can help you with an editorial strategy to get content into the hands of those visitors.