WordPress at a glance
function is not described

WP_Site::get_instance() public WP 4.5.0

Retrieves a site from the database by its ID.

{} It's a method of the class: WP_Site{}

No Hooks.

Return

WP_Site|false. The site's object if found. False if not.

Usage

$result = WP_Site::get_instance( $site_id );
$site_id(int) (required)
The ID of the site to retrieve.

Notes

  • Global. wpdb. $wpdb WordPress database abstraction object.

Changelog

Since 4.5.0 Introduced.

Code of WP_Site::get_instance() WP 5.7.2

<?php
public static function get_instance( $site_id ) {
	global $wpdb;

	$site_id = (int) $site_id;
	if ( ! $site_id ) {
		return false;
	}

	$_site = wp_cache_get( $site_id, 'sites' );

	if ( false === $_site ) {
		$_site = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM {$wpdb->blogs} WHERE blog_id = %d LIMIT 1", $site_id ) );

		if ( empty( $_site ) || is_wp_error( $_site ) ) {
			$_site = -1;
		}

		wp_cache_add( $site_id, $_site, 'sites' );
	}

	if ( is_numeric( $_site ) ) {
		return false;
	}

	return new WP_Site( $_site );
}