Consider the following when you use Microsoft Update to apply SQL Server Service Packs:
Service pack installations will be 'unattended' (quiet).
Microsoft Update will apply the SQL Server service pack to all instances of SQL Server that are installed on the target computer. Note The service pack is applied to all instances SQL Server that match the SQL Server version of the service pack.
Microsoft distributes fixes in service packs. Service packs keep a product current. They include hotfixes and fixes to issues that are reported through the Microsoft SQL Server community. Service packs may also include issues that our support organization feels have to be addressed. The most common metrics that are applied for triage of those items are customer call volume and customer satisfaction scores. These updates and components are conveniently bundled for easy downloading.
Service packs are cumulative. Each new service pack contains all the fixes that are in previous service packs, together with any new fixes. You do not have to install a previous service pack before you install the latest service pack.
KB2958069 How to obtain the latest SQL Server 2014 service pack
KB2755533 How to obtain the latest SQL Server 2012 service pack
KB2527041 How to obtain the latest SQL Server 2008 R2 service pack
Microsoft SQL Server 2008 Standard, Microsoft SQL Server 2008 Standard Edition for Small Business, Microsoft SQL Server 2008 Developer, Microsoft SQL Server 2008 Enterprise, Microsoft SQL Server 2008 Workgroup, Microsoft SQL Server 2008 Express, Microsoft SQL Server 2008 Express with Advanced Services, Microsoft SQL Server 2008 Web, Microsoft SQL Server 2008 Analysis Services, Microsoft SQL Server 2008 Reporting Services