Product variation WP_Query with a product category in Woocommerce

问题

With Woocommerce, I am trying to make a WP_Query for product variations post type with a product category 'Apple'.

$args = array(
    'product_cat'    => 'Apple',
    'post_type'      => array('product', 'product_variation'),
    'post_status'    => 'publish',
    'key'            => '_visibility',
    'value'          => 'visible',
    'posts_per_page' => 100,
    'taxonomy'       => 'pa_size',
    'meta_value'     => '39',
    'meta_query'     => array(
        array(
            'key'         => '_stock',
            'value'       => 0,
            'compare'     => '>'
        )
    )
);

But I can't get it work in this query. If I remove 'product_cat' => 'Apple', the query works. Why?

回答1:

There is many mistakes in this WP_Query regarding Woocommerce products:

For product category and product attribute you should better use normally a tax_query instead.
For Product visibility, since Woocommerce 3, it's handled by product_visibility taxonomy for 'exclude-from-search' and 'exclude-from-catalog' terms.

Important notes about Product variations:

Product categories (or product tags) are not handled by Product variations, but by the parent Variable product
Product attributes for variations are handled as post meta data with a meta_key prepended by "attribute_" and a met_value that is the term slug.
Product visibility is not handled in product variations, as they are not displayed in archives pages.
They are not displayed in archive pages (as mentioned before).

So when using a WP_Query, you can NOT query at the same time "product" post type and "product_variation" post type as they are really different.

To make your query work for "product_variation" post type, you need a little utility function that will get the parent variable product for a product category (or any custom taxonomy as Product tags…):

// Utility function to get the parent variable product IDs for a any term of a taxonomy
function get_variation_parent_ids_from_term( $term, $taxonomy, $type ){
    global $wpdb;

    return $wpdb->get_col( "
        SELECT DISTINCT p.ID
        FROM {$wpdb->prefix}posts as p
        INNER JOIN {$wpdb->prefix}posts as p2 ON p2.post_parent = p.ID
        INNER JOIN {$wpdb->prefix}term_relationships as tr ON p.ID = tr.object_id
        INNER JOIN {$wpdb->prefix}term_taxonomy as tt ON tr.term_taxonomy_id = tt.term_taxonomy_id
        INNER JOIN {$wpdb->prefix}terms as t ON tt.term_id = t.term_id
        WHERE p.post_type = 'product'
        AND p.post_status = 'publish'
        AND p2.post_status = 'publish'
        AND tt.taxonomy = '$taxonomy'
        AND t.$type = '$term'
    " );
}

Code goes in function.php file of your active child theme (or active theme). Tested and works. Necessary for the WP_Query below…

Here WP_Query code for Product variations (only) related to a specific product category and specific variation attribute values:

// Settings
$cat_name = 'Apple'; // Product category name
$attr_taxonomy = 'pa_size'; // Product attribute
$attribute_term_slugs = array('39'); // <== Need to be term SLUGs

$query = new WP_Query( array(
    'post_type'       => 'product_variation',
    'post_status'     => 'publish',
    'posts_per_page'  => 100,
    'post_parent__in' => get_variation_parent_ids_from_term( $cat_name, 'product_cat', 'name' ), // Variations
    'meta_query'      => array(
        'relation'    => 'AND',
        array(
            'key'     => '_stock',
            'value'   => 0,
            'compare' => '>'
        ),
        array( 
            'key'     => 'attribute_'.$attr_taxonomy, // Product variation attribute
            'value'   => $attribute_term_slugs, // Term slugs only
            'compare' => 'IN',
        ),
    ),
) );

// Display the queried products count
echo '<p>Product count: ' . $query->post_count . '<p>';

// Displaying raw output for posts
print_pr($query->posts);

Tested and works.

来源：https://stackoverflow.com/questions/49342704/product-variation-wp-query-with-a-product-category-in-woocommerce

标签

php

woocommerce

product

custom-taxonomy

variations