FacetWP Relevanssi integration

Setup

Because of the way Relevanssi plugs itself into WordPress core search, the Relevanssi add-on integration must be installed when you use FacetWP together with Relevanssi. Without the add-on, Search facets and the site-wide search results page will not work correctly.

When the Relevanssi add-on is activated, each Search facet will show a new “Relevanssi” option within its “Search engine” setting. This new “Relevanssi” engine must be selected, otherwise the facet will return no results. If you have reasons to want to use the “WP Default” engine instead, the only way to make this work is to disable Relevanssi on the page where the Search facet is placed.

If your site-wide search results page (the page with /?s=searchterm in the URL) has facets, the above is all you need to do. But if it does not have facets, the search result page will not show results. To fix this, you need to disable FacetWP on the search results page.

Turn off results snippets

Some users have reported issues with Relevanssi’s “Create custom search result snippets” feature.

If your results don’t show, try disabling that setting, as demonstrated below:

Relevanssi limits

Be aware that using Relevanssi may require large amounts (hundreds of MBs) of database space (for a reasonable estimate, multiply the size of your wp_posts database table by three). If your hosting setup has a limited amount of space for database tables, using Relevanssi may cause problems. The following information is from the Relevanssi site:

“The upper limit of how big a site Relevanssi can support depends on your hardware. On shared hosting accounts with limited resources, tens of thousands of posts can be too much. If your hardware is solid, especially your database, there’s probably no upper boundary. The biggest site we’ve heard run Relevanssi without problems had two million posts, using a dedicated database server with SSD drives.”

Fix “no results” on the search results page

If you have the FacetWP Relevanssi integration add-on installed, and your search results page (the page with /?s=searchterm in the URL) does not have facets, the search will not work properly and show no results.

This is caused by FacetWP’s integration having to intercept the search query before it can know if facets are being used on the page. To fix this issue, you have to disable FacetWP for the search results page only, by adding the following code to your (child) theme’s functions.php:

Using Relevanssi with WooCommerce

If you are using Relevanssi together with WooCommerce, some things will not work immediately.

This article in the Relevanssi documentation gives a good overview of common compatibility issues and their fixes.

Fix search results for WooCommerce product SKUs

If you are using Relevanssi with WooCommerce, with product variations enabled, you may run into issues when searching variation product SKUs with the Search facet.

Relevanssi can index product and product variation SKUs for WooCommerce products: just add _sku to the list of custom fields to index. But Relevanssi will index SKUs for the variations only, so the parent product will not be found when searching for the variation SKU.

The following code (source) uses the relevanssi_content_to_index filter hook to index the product variation SKUs for the main product, so you will be able to find the parent product when searching for the variation SKU.

Add this code to your (child) theme’s functions.php, rebuild the Relevanssi index and re-index FacetWP:

How to disable Relevanssi on certain pages

If you need to disable Relevanssi on specific pages or templates, all you need to do is unhook two Relevanssi filters. To do so, add the following code to your (child) theme’s functions.php. If you want to apply this code only to specific pages or templates, use a Conditional Tag. In this example the code is only applied to a page with ID 4814.

With this code in place, it is also possible to use the “WP Default” Search engine setting in Search facets when you have Relevanssi installed, which normally does not work.

Change the minimum word length

By default, Relevanssi does not index words shorter than three characters. So search terms with less than three characters will not return any results in Search facets that use the Relevanssi engine.

You can change this with the “Minimum word length” setting. To find this setting, navigate to
Settings > Relevanssi > Indexing, then scroll down to “Advanced indexing settings”, then click “Show advanced settings”:

After making changes to this setting, make sure to rebuild Relavanssi’s index.

If you want to allow one-letter searches, you can do so with the “relevanssi_block_one_letter_searches” hook:

add_filter( 'relevanssi_block_one_letter_searches', '__return_false' );

Note that (according to the above-linked documentation) this filter does not work if fuzzy matching is enabled (in Settings > Relevanssi > Searching > Keyword matching > “Partial words”).