title: "sys.dm_db_session_space_usage (Transact-SQL) | Microsoft Docs" ms.custom: "" ms.date: "11/16/2015" ms.prod: "sql" ms.prod_service: "database-engine, sql-database, sql-data-warehouse, pdw" ms.service: "" ms.component: "dmv's" ms.reviewer: "" ms.suite: "sql" ms.technology:
- "database-engine" ms.tgt_pltfrm: "" ms.topic: "language-reference" f1_keywords:
- "dm_db_session_space_usage_TSQL"
- "dm_db_session_space_usage"
- "sys.dm_db_session_space_usage"
- "sys.dm_db_session_space_usage_TSQL" dev_langs:
- "TSQL" helpviewer_keywords:
- "sys.dm_db_session_space_usage dynamic management view" ms.assetid: a67a6045-8e14-460a-9fe3-912b846c08c1 caps.latest.revision: 34 author: "stevestein" ms.author: "sstein" manager: "craigg" monikerRange: ">= aps-pdw-2016 || = azuresqldb-current || = azure-sqldw-latest || >= sql-server-2016 || = sqlallproducts-allversions"
[!INCLUDEtsql-appliesto-ss2008-all-md]
Returns the number of pages allocated and deallocated by each session for the database.
Note
This view is applicable only to the tempdb database.
Note
To call this from [!INCLUDEssSDWfull] or [!INCLUDEssPDW], use the name sys.dm_pdw_nodes_db_session_space_usage.
| Column name | Data type | Description |
|---|---|---|
| session_id | smallint | Session ID. session_id maps to session_id in sys.dm_exec_sessions. |
| database_id | smallint | Database ID. |
| user_objects_alloc_page_count | bigint | Number of pages reserved or allocated for user objects by this session. |
| user_objects_dealloc_page_count | bigint | Number of pages deallocated and no longer reserved for user objects by this session. |
| internal_objects_alloc_page_count | bigint | Number of pages reserved or allocated for internal objects by this session. |
| internal_objects_dealloc_page_count | bigint | Number of pages deallocated and no longer reserved for internal objects by this session. |
| user_objects_deferred_dealloc_page_count | bigint | Number of pages which have been marked for deferred deallocation. Note: Introduced in service packs for [!INCLUDEssSQL11] and [!INCLUDEssSQL14]. |
| pdw_node_id | int | Applies to: [!INCLUDEssSDWfull], [!INCLUDEssPDW] The identifier for the node that this distribution is on. |
On [!INCLUDEssNoVersion_md], requires VIEW SERVER STATE permission.
On [!INCLUDEssSDS_md], requires the VIEW DATABASE STATE permission in the database.
IAM pages are not included in any of the allocation or deallocation counts reported by this view.
Page counters are initialized to zero (0) at the start of a session. The counters track the total number of pages that have been allocated or deallocated for tasks that are already completed in the session. The counters are updated only when a task ends; they do not reflect running tasks.
A session can have multiple requests active at the same time. A request can start multiple threads, tasks, if it is a parallel query.
For more information about the sessions, requests, and tasks, see sys.dm_exec_sessions (Transact-SQL), sys.dm_exec_requests (Transact-SQL), and sys.dm_os_tasks (Transact-SQL).
The following objects are included in the user object page counters:
-
User-defined tables and indexes
-
System tables and indexes
-
Global temporary tables and indexes
-
Local temporary tables and indexes
-
Table variables
-
Tables returned in the table-valued functions
Internal objects are only in tempdb. The following objects are included in the internal object page counters:
-
Work tables for cursor or spool operations and temporary large object (LOB) storage
-
Work files for operations such as a hash join
-
Sort runs
| From | To | Relationship |
|---|---|---|
| dm_db_session_space_usage.session_id | dm_exec_sessions.session_id | One-to-one |
Dynamic Management Views and Functions (Transact-SQL)
Database Related Dynamic Management Views (Transact-SQL)
sys.dm_exec_sessions (Transact-SQL)
sys.dm_exec_requests (Transact-SQL)
sys.dm_os_tasks (Transact-SQL)
sys.dm_db_task_space_usage (Transact-SQL)
sys.dm_db_file_space_usage (Transact-SQL)