title: "SESSION_ID (Transact-SQL) | Microsoft Docs" ms.custom: "" ms.date: "02/23/2018" ms.prod: "sql" ms.prod_service: "sql-data-warehouse, pdw" ms.service: "" ms.component: "t-sql|functions" ms.reviewer: "" ms.suite: "sql" ms.technology:
- "database-engine" ms.tgt_pltfrm: "" ms.topic: "language-reference" dev_langs:
- "TSQL" author: "barbkess" ms.author: "barbkess" manager: "craigg" ms.workload: "Inactive" monikerRange: ">= aps-pdw-2016 || = azure-sqldw-latest || = sqlallproducts-allversions"
[!INCLUDEtsql-appliesto-xxxxxx-xxxx-asdw-pdw-md]
Returns the ID of the current [!INCLUDEssSDW] or [!INCLUDEssPDW_md] session.
Transact-SQL Syntax Conventions (Transact-SQL)
-- Azure SQL Data Warehouse and Parallel Data Warehouse
SESSION_ID ( )
Returns an nvarchar(32) value.
The session ID is assigned to each user connection when the connection is made. It persists for the duration of the connection. When the connection ends, the session ID is released.
The session ID begins with the alphabetical characters 'SID'. These are case-sensitive and must be capitalized when session ID is used in [!INCLUDEDWsql] commands.
You can query the view sys.dm_pdw_exec_sessions to retrieve the same information as this function.
The following example returns the current session ID.
SELECT SESSION_ID();