// Update product attributes which use this taxonomy.
			$old_taxonomy_name = 'pa_' . $old_slug;
			$new_taxonomy_name = 'pa_' . $data['attribute_name'];
			$old_attribute_key = sanitize_title( $old_taxonomy_name ); // @see WC_Product::set_attributes().
			$new_attribute_key = sanitize_title( $new_taxonomy_name ); // @see WC_Product::set_attributes().
			$metadatas         = $wpdb->get_results(
				$wpdb->prepare(
					"SELECT post_id, meta_value FROM {$wpdb->postmeta} WHERE meta_key = '_product_attributes' AND meta_value LIKE %s",
					'%' . $wpdb->esc_like( $old_taxonomy_name ) . '%'
				),
				ARRAY_A
			);
			foreach ( $metadatas as $metadata ) {
				$product_id        = $metadata['post_id'];
				$unserialized_data = maybe_unserialize( $metadata['meta_value'] );

				if ( ! $unserialized_data || ! is_array( $unserialized_data ) || ! isset( $unserialized_data[ $old_attribute_key ] ) ) {
					continue;
				}

				$unserialized_data[ $new_attribute_key ] = $unserialized_data[ $old_attribute_key ];
				unset( $unserialized_data[ $old_attribute_key ] );
				$unserialized_data[ $new_attribute_key ]['name'] = $new_taxonomy_name;
				update_post_meta( $product_id, '_product_attributes', wp_slash( $unserialized_data ) );
			}

			// Update variations which use this taxonomy.
			$wpdb->update(
				$wpdb->postmeta,
				array( 'meta_key' => 'attribute_pa_' . sanitize_title( $data['attribute_name'] ) ), // WPCS: slow query ok.
				array( 'meta_key' => 'attribute_pa_' . sanitize_title( $old_slug ) ) // WPCS: slow query ok.
			);
		}
	}

	// Clear cache and flush rewrite rules.
	wp_schedule_single_event( time(), 'woocommerce_flush_rewrite_rules' );
	delete_transient( 'wc_attribute_taxonomies' );
	WC_Cache_Helper::invalidate_cache_group( 'woocommerce-attributes' );

	return $id;
}

/**
 * Update an attribute.
 *
 * For available args see wc_create_attribute().
 *
 * @since  3.2.0
 * @param  int   $id   Attribute ID.
 * @param  array $args Attribute arguments.
 * @return int|WP_Error
 */
function wc_update_attribute( $id, $args ) {
	global $wpdb;

	$attribute = wc_get_attribute( $id );

	$args['id'] = $attribute ? $attribute->id : 0;

	if ( $args['id'] && empty( $args['name'] ) ) {
		$args['name'] = $attribute->name;
	}

	$args['old_slug'] = $wpdb->get_var(
		$wpdb->prepare(
			"
				SELECT attribute_name
				FROM {$wpdb->prefix}woocommerce_attribute_taxonomies
				WHERE attribute_id = %d
			",
			$args['id']
		)
	);

	return wc_create_attribute( $args );
}

/**
 * Delete attribute by ID.
 *
 * @since  3.2.0
 * @param  int $id Attribute ID.
 * @return bool
 */
function wc_delete_attribute( $id ) {
	global $wpdb;

	$name = $wpdb->get_var(
		$wpdb->prepare(
			"
			SELECT attribute_name
			FROM {$wpdb->prefix}woocommerce_attribute_taxonomies
			WHERE attribute_id = %d
			",
			$id
		)
	);

	$taxonomy = wc_attribute_taxonomy_name( $name );

	/**
	 * Before deleting an attribute.
	 *
	 * @param int    $id       Attribute ID.
	 * @param string $name     Attribute name.
	 * @param string $taxonomy Attribute taxonomy name.
	 */
	do_action( 'woocommerce_before_attribute_delete', $id, $name, $taxonomy );

	if ( $name && $wpdb->query( $wpdb->prepare( "DELETE FROM {$wpdb->prefix}woocommerce_attribute_taxonomies WHERE attribute_id = %d", $id ) ) ) {
		if ( taxonomy_exists( $taxonomy ) ) {
			$terms = get_terms( $taxonomy, 'orderby=name&hide_empty=0' );
			foreach ( $terms as $term ) {
				wp_delete_term( $term->term_id, $taxonomy );
			}
		}

		/**
		 * After deleting an attribute.
		 *
		 * @param int    $id       Attribute ID.
		 * @param string $name     Attribute name.
		 * @param string $taxonomy Attribute taxonomy name.
		 */
		do_action( 'woocommerce_attribute_deleted', $id, $name, $taxonomy );
		wp_schedule_single_event( time(), 'woocommerce_flush_rewrite_rules' );
		delete_transient( 'wc_attribute_taxonomies' );
		WC_Cache_Helper::invalidate_cache_group( 'woocommerce-attributes' );

		return true;
	}

	return false;
}

/**
 * Get an unprefixed product attribute name.
 *
 * @since 3.6.0
 *
 * @param  string $attribute_name Attribute name.
 * @return string
 */
function wc_attribute_taxonomy_slug( $attribute_name ) {
	$prefix      = WC_Cache_Helper::get_cache_prefix( 'woocommerce-attributes' );
	$cache_key   = $prefix . 'slug-' . $attribute_name;
	$cache_value = wp_cache_get( $cache_key, 'woocommerce-attributes' );

	if ( false !== $cache_value ) {
		return $cache_value;
	}

	$attribute_name = wc_sanitize_taxonomy_name( $attribute_name );
	$attribute_slug = 0 === strpos( $attribute_name, 'pa_' ) ? substr( $attribute_name, 3 ) : $attribute_name;
	wp_cache_set( $cache_key, $attribute_slug, 'woocommerce-attributes' );

	return $attribute_slug;
}