wpdb::set_blog_id( int $blog_id, int $network_id = 0 ): int

1043	public function set_blog_id( $blog_id, $network_id = 0 ) {1044		if ( ! empty( $network_id ) ) {1045			$this->siteid = $network_id;1046		}1047 1048		$old_blog_id  = $this->blogid;1049		$this->blogid = $blog_id;1050 1051		$this->prefix = $this->get_blog_prefix();1052 1053		foreach ( $this->tables( 'blog' ) as $table => $prefixed_table ) {1054			$this->$table = $prefixed_table;1055		}1056 1057		foreach ( $this->tables( 'old' ) as $table => $prefixed_table ) {1058			$this->$table = $prefixed_table;1059		}1060 1061		return $old_blog_id;1062	}