Use . or (local) or localhost for server name if您将服务器安装为默认实例.

Use . or (local) or localhost for server name if you installed the server as default instance.

如果您有 SQL Express，请使用 .\sqlexpress 或 localhost\sqlexpress.

Use .\sqlexpress or localhost\sqlexpress if you have SQL Express.

服务器名称语法为

Servername\InstanceName

如果实例是默认的，你只使用服务器名.
对于 SQL Express，实例名称默认为 sqlexpress.

If the instance is default you use just Servername.
For SQL Express, instance name is sqlexpress by default.