WP_Query_WithRelevance

Wordpress WP_Query subclass which adds "relevance" as a new orderby option.

Relevance is calculated by a combination of factors:

Overlap between the post taxonomies and taxonomies requested in tax_query filter
Frequency of keywords in the post title and content, keywords given by the s filter

This may be used with a different orderby value in order, in which case it will perform a regular WP_Query() with no additional overhead. Therefore, full compatibility is provided for both relevance-sorted queries and "regular" queries.

Basic Usage

Place the wpquery_withrelevance.php file into your file structure, and then load it in your functions.php file. You now have access to WP_Query_WithRelevance()

The query takes typical WP_Query() filters and only invokes its special behavior when orderby = keyword is given.

require_once 'wpquery_withrelevance.php';

$filter = array( // basic filter: published posts
    'post_type' => 'post',
	'post_status' => 'publish',
    'posts_per_page' => 50,
);

$filter['s'] = "Mayonnaise Conspiracy";  // a keyword filter

$filter['tax_query'] = array(  // filter posts having any of these tags
    array(
    	'taxonomy' => 'tags',
    	'field'    => 'slug',
    	'operator' => 'IN',
    	'terms'    => array('sandwiches', 'condiments', 'lunch'),
    ),
);

if ($_GET['sorting']) == 'best') {
    $filter['orderby'] = "relevance"; // this is the magic word!
}
else {
    $filter['orderby'] = "title"; // but it's also okay to not use relevance, a regular WP_Query() is done
}

$query = new WP_Query_WithRelevance($filter);

If orderby is any value except "relevance" then relevance calculation is skipped entirely. This is effectively the same as running a regular WP_Query() and provides compatibility so you don't need to use a different interface, nor suffer a performance hit, if you want to sort by "regular" capabilities.

Ordering is By Relevance Only

Multi-field sorting is not supported by WP_Query_WithRelevance()

The orderby field must be exactly the word "relevance" and ordering is done by relevance score only. No additional ordering may be specified.

Adjusting the Relevance Scoring

The built-in scoring weights should work well for most folks. But, you may fine-tune the relevance scoring by supplying an additional relevance_scoring structure. This specifies the weighting value to give to keywords matched in the title, keywords matched in the content body, taxonomies in common, and so forth.

$filter['relevance_scoring'] = array(
    // weighting by taxonomy: the built in "tags" taxo plus a custom taxo, with different weights
    'tax_query' => array(
        'tags' => 10.0,
        'authors' => 25.0,
    ),
    // the points per word occurrence, in post title and content
    'title_keyword' => 1.0,
    'content_keyword' => 0.25,
);

Credits

This was written by Greg Allensworth at GreenInfo Network

This is all-original code, but was inspired and guided by reference to https://github.com/mannieschumpert/wp-relevance-query

GreenInfo-Network/WP_Query_WithRelevance

WP_Query_WithRelevance

Basic Usage

Ordering is By Relevance Only

Adjusting the Relevance Scoring

Credits