Microsoft SQL Server 2012 uses services
to provide the underlying functionality that enables you to access SQL Server.
A service is a process or function that runs autonomously in the background under Windows 10 or Windows Server 2016.
A service must start with a user name and password (known as a security context
) to function.
The user name and password that you specify must correspond to a person who has access to the resources used by the service.
The following four services are available in Microsoft SQL Server 2012:
- MSDTC:Used to manage distributed transactions.
(You will learn more about distributed transactions in the third course in this series.)
- MSSQLServer:Enables SQL Server 2012 to function. If the MSSQLServer service is not running, SQL Server 2012 will not respond to queries and requests.
- SQLServerAgent:Handles all scheduling within SQL Server 2012. (You will learn more about scheduling later in this course.)
- Microsoft Search:Search engine service for use with full-text searches. This service is only available if you have chosen to install the full-text search when you initially installed SQL Server 2012.
Each of these four services can be in one of three states:
- Running:Fully operational and able to provide the functionality designed for the service.
- Paused:Allows existing users to complete tasks, but does not allow any new connections.
- Stopped:Does not perform any of the functionality designed for the service.
The following applet illustrates the four services in the Running state under Windows NT. Click the forward and back arrows to flip through the images. (Note: If all you see is a gray box, click Non-Java version to see the images in sequence on a new page.)