CONTEXT_INFO (Transact-SQL)

The value of context_info, or NULL if context_info was not set.

Multiple active result sets (MARS) enables applications to run multiple batches, or requests, at the same time on the same connection. When one of the batches on a MARS connection runs SET CONTEXT_INFO, the new context value is returned by the CONTEXT_INFO function when it is run in the same batch as the SET statement. The new value is not returned by the CONTEXT_INFO function run in one or more of the other batches on the connection, unless they started after the batch that ran the SET statement completed.

Requires no special permissions. The context information is also stored in the sys.dm_exec_requests, sys.dm_exec_sessions, and sys.sysprocesses system views, but querying the views directly requires SELECT and VIEW SERVER STATE permissions.

The following simple example sets the context_info value to 0x1256698456, and then uses the CONTEXT_INFO function to retrieve the value.

SET CONTEXT_INFO 0x1256698456
GO
SELECT CONTEXT_INFO()
GO

Reference