Index: wp-includes/date.php
===================================================================
--- wp-includes/date.php	(revision 37273)
+++ wp-includes/date.php	(working copy)
@@ -491,7 +491,7 @@
 		$valid_columns = array(
 			'post_date', 'post_date_gmt', 'post_modified',
 			'post_modified_gmt', 'comment_date', 'comment_date_gmt',
-			'user_registered',
+			'user_registered', 'registered', 'last_updated',
 		);
 
 		// Attempt to detect a table prefix.
@@ -525,6 +525,10 @@
 				$wpdb->users => array(
 					'user_registered',
 				),
+				$wpdb->blogs => array(
+					'registered',
+					'last_updated',
+				),
 			);
 
 			// If it's a known column name, add the appropriate table prefix.
Index: wp-includes/ms-blogs.php
===================================================================
--- wp-includes/ms-blogs.php	(revision 37273)
+++ wp-includes/ms-blogs.php	(working copy)
@@ -468,6 +468,101 @@
 }
 
 /**
+ * Retrieves site data given a site ID or site object.
+ *
+ * If an object is passed then the site data will be cached and then returned
+ * after being passed through a filter. If the site is empty, then the global
+ * site variable will be used, if it is set.
+ *
+ * @since 4.6.0
+ *
+ * @global WP_Site $site
+ *
+ * @param WP_Site|string|int $site Site to retrieve.
+ * @param string $output Optional. OBJECT or ARRAY_A or ARRAY_N constants.
+ *
+ * @return WP_Site|array|null Depends on $output value.
+ */
+function get_site( &$site = null, $output = OBJECT ) {
+	global $current_blog;
+	if ( empty( $site ) && isset( $current_blog ) ) {
+		$site = $current_blog;
+	}
+
+	if ( $site instanceof WP_Site ) {
+		$_site = $site;
+	} elseif ( is_object( $site ) ) {
+		$_site = new WP_Site( $site );
+	} else {
+		$_site = WP_Site::get_instance( $site );
+	}
+
+	if ( ! $_site ) {
+		return null;
+	}
+
+	/**
+	 * Fires after a site is retrieved.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @param mixed $_site Site data.
+	 */
+	$_site = apply_filters( 'get_site', $_site );
+
+	if ( $output == OBJECT ) {
+		return $_site;
+	} elseif ( $output == ARRAY_A ) {
+		return $_site->to_array();
+	} elseif ( $output == ARRAY_N ) {
+		return array_values( $_site->to_array() );
+	}
+
+	return $_site;
+}
+
+/**
+ * Adds any sites from the given ids to the cache that do not already exist in cache
+ *
+ * @since 4.6.0
+ * @access private
+ *
+ * @see update_site_cache()
+ *
+ * @global wpdb $wpdb WordPress database abstraction object.
+ *
+ * @param array $ids ID list.
+ */
+function _prime_site_caches( $ids ) {
+	global $wpdb;
+
+	$non_cached_ids = _get_non_cached_ids( $ids, 'sites' );
+	if ( ! empty( $non_cached_ids ) ) {
+		$fresh_sites = $wpdb->get_results( sprintf( "SELECT * FROM $wpdb->blogs WHERE blog_id IN (%s)", join( ",", $non_cached_ids ) ) );
+
+		update_site_cache( $fresh_sites );
+	}
+}
+
+/**
+ * Updates sites in cache.
+ *
+ * @since 4.6.0
+ *
+ * @param array $sites Array of site objects, passed by reference.
+ */
+function update_site_cache( &$sites ) {
+	if ( ! $sites ) {
+		return;
+	}
+
+	foreach ( $sites as $site ) {
+		wp_cache_add( $site->blog_id, $site, 'sites' );
+		wp_cache_add( $site->blog_id . 'short', $site, 'blog-details' );
+	}
+}
+
+/**
  * Retrieve option value for a given blog id based on name of option.
  *
  * If the option does not exist or does not have a value, then the return value
Index: wp-settings.php
===================================================================
--- wp-settings.php	(revision 37273)
+++ wp-settings.php	(working copy)
@@ -99,6 +99,7 @@
 
 // Initialize multisite if enabled.
 if ( is_multisite() ) {
+	require( ABSPATH . WPINC . '/class-wp-site-query.php' );
 	require( ABSPATH . WPINC . '/ms-blogs.php' );
 	require( ABSPATH . WPINC . '/ms-settings.php' );
 } elseif ( ! defined( 'MULTISITE' ) ) {