<?php

$wpdb->add_database( array(
	'host'     => 'global.db.example.com',
	'user'     => 'globaluser',
	'password' => 'globalpassword',
	'name'     => 'globaldb',
) );

$wpdb->add_database( array(
	'host'     => '192.168.1.5',
	'user'     => DB_USER,
	'password' => DB_PASSWORD,
	'name'     => 'mycustomdatabase',
	'write'    => 1,
	'read'     => 1,
	'dataset'  => 'customdataset',
	'timeout'  => 0.5,
) );


$wpdb->add_table( 'customdataset', 'wp_my_custom_table' );