
Categories of Configuration Options
Configuration options take effect either:
-
Immediately after setting the option and issuing the RECONFIGURE (or in some cases, RECONFIGURE WITH OVERRIDE) statement.
-or-
-
After performing the above actions and restarting the instance of SQL Server.
To configure an advanced option with sp_configure, you must first run sp_configure with the 'show advanced options' option set to 1, and then run RECONFIGURE:
sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO
sp_configure 'cursor threshold', 0;
GO
RECONFIGURE;
GO
In the previous example, reconfiguring the cursor threshold option takes place immediately. The new value for cursor threshold appears in the configuration options value_in_use column and the value column.
Options that require a restart of the instance of SQL Server will initially show the changed value only in the value column. After restart, the new value will appear in both the value column and the value_in_use column.
Some options require a server restart before the new configuration value takes effect. If you set the new value and run sp_configure before restarting the server, the new value appears in the configuration options value column, but not in the value_in_use column. After restarting the server, the new value appears in the value_in_use column.
Self-configuring options are those that SQL Server adjusts according to the needs of the system. In most cases, this eliminates the need for setting the values manually. Examples include the min server memory and max server memory options and the user connections option.