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SQL Server, User Settable object

Applies to: SQL Server

The User Settable object in Microsoft SQL Server allows you to create custom counter instances. Use custom counter instances to monitor aspects of the server not monitored by existing counters, such as components unique to your SQL Server database (for example, the number of customer orders logged or the product inventory).

The User Settable object contains 10 instances of the query counter: User counter 1 through User counter 10. These counters map to the SQL Server stored procedures sp_user_counter1 through sp_user_counter10. As these stored procedures are executed by user applications, the values set by the stored procedures are displayed in System Monitor. A counter can monitor any single integer value (for example, a stored procedure that counts how many orders for a particular product have occurred in one day).

Note

The user counter stored procedures are not polled automatically by System Monitor. They must be explicitly executed by a user application for the counter values to be updated. Use a trigger to update the value of the counter automatically.

This table describes the SQL Server User Settable object.

SQL Server User Settable counters Description
Query The User Settable object contains the query counter. Users configure each User counter within the query object. Each counter is an integer data type.

This table describes the instances of the Query counter.

Query counter instances Description
User counter 1 Defined using sp_user_counter1.
User counter 2 Defined using sp_user_counter2.
User counter 3 Defined using sp_user_counter3.
...
User counter 10 Defined using sp_user_counter10.

Set user counter value

To make use of the user counter stored procedures, execute them from your own application with a single integer parameter representing the new value for the counter. For example, to set User counter 1 to the value 10, execute this Transact-SQL statement:

EXECUTE dbo.sp_user_counter1 10;

The user counter stored procedures can be called from anywhere other stored procedures can be called, such as your own stored procedures. For example, you can create the following stored procedure to count the number of connections and attempted connections since an instance of SQL Server was started:

DROP PROC My_Proc;  
GO  
CREATE PROC My_Proc  
AS   
   EXECUTE dbo.sp_user_counter1 @@CONNECTIONS;  
GO  

The @@CONNECTIONS function returns the number of connections or attempted connections since an instance of SQL Server started. This value is passed to the sp_user_counter1 stored procedure as the parameter.

Important

Make the queries defined in the user counter stored procedures as simple as possible. Memory-intensive queries that perform substantial sort or hash operations or queries that perform large amounts of I/O are expensive to execute and can impact performance.

Monitor example

You begin to explore the counters in this object using this T-SQL query on the sys.dm_os_performance_counters dynamic management view:

SELECT * FROM sys.dm_os_performance_counters
WHERE object_name LIKE '%User Settable%';

Permissions

The stored procedure sp_user_counter is available for all users but can be restricted for any query counter.