Applies To: SQL Server 2014, SQL Server 2016 Preview
Topic Status: Some information in this topic is preview and subject to change in future releases. Preview information describes new features or changes to existing features in Microsoft SQL Server 2016 Community Technology Preview 2 (CTP2).
SESSION_USER returns the user name of the current context in the current database.
Applies to: SQL Server (SQL Server 2008 through current version), Azure SQL Database, Azure SQL Data Warehouse Public Preview.
Use SESSION_USER with DEFAULT constraints in either the CREATE TABLE or ALTER TABLE statements, or use it as any standard function. SESSION_USER can be inserted into a table when no default value is specified. This function takes no arguments. SESSION_USER can be used in queries.
If SESSION_USER is called after a context switch, SESSION_USER will return the user name of the impersonated context.
A. Using SESSION_USER to return the user name of the current session
The following example declares a variable as nchar, assigns the current value of SESSION_USER to that variable, and then prints the variable with a text description.
DECLARE @session_usr nchar(30); SET @session_usr = SESSION_USER; SELECT 'This session''s current user is: '+ @session_usr; GO
This is the result set when the session user is Surya:
This session's current user is: Surya
(1 row(s) affected)
B. Using SESSION_USER with DEFAULT constraints
The following example creates a table that uses SESSION_USER as a DEFAULT constraint for the name of the person who records receipt of a shipment.
USE AdventureWorks2012; GO CREATE TABLE deliveries3 ( order_id int IDENTITY(5000, 1) NOT NULL, cust_id int NOT NULL, order_date smalldatetime NOT NULL DEFAULT GETDATE(), delivery_date smalldatetime NOT NULL DEFAULT DATEADD(dd, 10, GETDATE()), received_shipment nchar(30) NOT NULL DEFAULT SESSION_USER ); GO
Records added to the table will be stamped with the user name of the current user. In this example, Wanida, Sylvester, and Alejandro verify receipt of shipments. This can be emulated by switching user context by using EXECUTE AS.
EXECUTE AS USER = 'Wanida' INSERT deliveries3 (cust_id) VALUES (7510); INSERT deliveries3 (cust_id) VALUES (7231); REVERT; EXECUTE AS USER = 'Sylvester' INSERT deliveries3 (cust_id) VALUES (7028); REVERT; EXECUTE AS USER = 'Alejandro' INSERT deliveries3 (cust_id) VALUES (7392); INSERT deliveries3 (cust_id) VALUES (7452); REVERT; GO
The following query selects all information from the deliveries3 table.
SELECT order_id AS 'Order #', cust_id AS 'Customer #', delivery_date AS 'When Delivered', received_shipment AS 'Received By' FROM deliveries3 ORDER BY order_id; GO
Here is the result set.
Order # Customer # When Delivered Received By
-------- ---------- ------------------- -----------
5000 7510 2005-03-16 12:02:14 Wanida
5001 7231 2005-03-16 12:02:14 Wanida
5002 7028 2005-03-16 12:02:14 Sylvester
5003 7392 2005-03-16 12:02:14 Alejandro
5004 7452 2005-03-16 12:02:14 Alejandro
(5 row(s) affected)