From 63664c12821fd46ed3ac46310ccf59b2631c1d69 Mon Sep 17 00:00:00 2001
From: Jeremy Felt <jeremy.felt@gmail.com>
Date: Tue, 20 Sep 2016 18:47:27 +0000
Subject: [PATCH] Multisite: Use `get_networks()` in `get_main_network_id()`.

The manual query for the main network ID can now be replaced with a cached `get_networks()` query. This allows us to eliminate the `primary_network_id` cache key entirely.

Props spacedmonkey.
Fixes #37218.

Built from https://develop.svn.wordpress.org/trunk@38632


git-svn-id: http://core.svn.wordpress.org/trunk@38575 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/functions.php | 12 ++----------
 wp-includes/version.php   |  2 +-
 2 files changed, 3 insertions(+), 11 deletions(-)

diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index 6e2fce9718..360a2db83e 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -4353,13 +4353,9 @@ function is_main_network( $network_id = null ) {
  *
  * @since 4.3.0
  *
- * @global wpdb $wpdb WordPress database abstraction object.
- *
  * @return int The ID of the main network.
  */
 function get_main_network_id() {
-	global $wpdb;
-
 	if ( ! is_multisite() ) {
 		return 1;
 	}
@@ -4372,12 +4368,8 @@ function get_main_network_id() {
 		// If the current network has an ID of 1, assume it is the main network.
 		$main_network_id = 1;
 	} else {
-		$main_network_id = wp_cache_get( 'primary_network_id', 'site-options' );
-
-		if ( false === $main_network_id ) {
-			$main_network_id = (int) $wpdb->get_var( "SELECT id FROM {$wpdb->site} ORDER BY id LIMIT 1" );
-			wp_cache_add( 'primary_network_id', $main_network_id, 'site-options' );
-		}
+		$_networks = get_networks( array( 'fields' => 'ids', 'number' => 1 ) );
+		$main_network_id = array_shift( $_networks );
 	}
 
 	/**
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 592e879b0b..a3963201d0 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.7-alpha-38631';
+$wp_version = '4.7-alpha-38632';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.