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Copy file name to clipboardExpand all lines: docs/database-engine/configure-windows/configure-the-max-degree-of-parallelism-server-configuration-option.md
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# Configure the max degree of parallelism Server Configuration Option
This topic describes how to configure the **max degree of parallelism (MAXDOP)** server configuration option in [!INCLUDE[ssCurrent](../../includes/sscurrent-md.md)] by using [!INCLUDE[ssManStudioFull](../../includes/ssmanstudiofull-md.md)] or [!INCLUDE[tsql](../../includes/tsql-md.md)]. When an instance of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] runs on a computer that has more than one microprocessor or CPU, it detects the best degree of parallelism, that is, the number of processors employed to run a single statement, for each parallel plan execution. You can use the **max degree of parallelism** option to limit the number of processors to use in parallel plan execution. [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] considers parallel execution plans for queries, index data definition language (DDL) operations, parallel insert, online alter column, parallel stats collection, and static and keyset-driven cursor population.
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This topic describes how to configure the **max degree of parallelism (MAXDOP)** server configuration option in [!INCLUDE[ssCurrent](../../includes/sscurrent-md.md)] by using [!INCLUDE[ssManStudioFull](../../includes/ssmanstudiofull-md.md)] or [!INCLUDE[tsql](../../includes/tsql-md.md)]. When an instance of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] runs on a computer that has more than one microprocessor or CPU, it detects the degree of parallelism, that is, the number of processors employed to run a single statement, for each parallel plan execution. You can use the **max degree of parallelism** option to limit the number of processors to use in parallel plan execution. [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] considers parallel execution plans for queries, index data definition language (DDL) operations, parallel inserts, online alter column, parallel stats collection, and static and keyset-driven cursor population.
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## <aname="BeforeYouBegin"></a> Before You Begin
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### <aname="Restrictions"></a> Limitations and Restrictions
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- If the affinity mask option is not set to the default, it may restrict the number of processors available to [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] on symmetric multiprocessing (SMP) systems.
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- The **max degree of parallelism (MAXDOP)** limit is set per [task](../../relational-databases/system-dynamic-management-views/sys-dm-os-tasks-transact-sql.md). It is not a per [request](../../relational-databases/system-dynamic-management-views/sys-dm-exec-requests-transact-sql.md) or per query limit. This means that during a parallel query execution, a single request can spawn multiple tasks which are assigned to a scheduler. For more information, see the [Thread and Task Architecture Guide](../../relational-databases/thread-and-task-architecture-guide.md).
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### <aname="Recommendations"></a> Recommendations
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- In addition to queries and index operations, this option also controls the parallelism of DBCC CHECKTABLE, DBCC CHECKDB, and DBCC CHECKFILEGROUP. You can disable parallel execution plans for these statements by using trace flag 2528. For more information, see [Trace Flags (Transact-SQL)](../../t-sql/database-console-commands/dbcc-traceon-trace-flags-transact-sql.md).
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> [!TIP]
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> To accomplish this at the query level, use the **MAXDOP**[query hint](../../t-sql/queries/hints-transact-sql-query.md).
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> To accomplish this at the database level, use the **MAXDOP**[database scoped configuration](../../t-sql/statements/alter-database-scoped-configuration-transact-sql.md).
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> To accomplish this at the workload level, use the **MAX_DOP**[Resource Governor workload group configuration option](../../t-sql/statements/create-workload-group-transact-sql.md).
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### <aname="Guidelines"></a> Guidelines
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Starting with [!INCLUDE[ssSQL15](../../includes/sssql15-md.md)], during service startup if the [!INCLUDE[ssde_md](../../includes/ssde_md.md)] detects more than eight physical cores per NUMA node or socket at startup, soft-NUMA nodes are created automatically by default. The [!INCLUDE[ssde_md](../../includes/ssde_md.md)] places logical processors from the same physical core into different soft-NUMA nodes. The recommendations in the table below are aimed at keeping all the worker threads of a parallel query within the same soft-NUMA node. This will improve the performance of the queries and distribution of worker threads across the NUMA nodes for the workload. For more information, see [Soft-NUMA](../../database-engine/configure-windows/soft-numa-sql-server.md).
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The setting takes effect immediately without restarting the server.
Returns information about each request that is executing within[!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)].
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Returns information about each request that is executing in[!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)]. For more information about requests, see the [Thread and Task Architecture Guide](../../relational-databases/thread-and-task-architecture-guide.md).
|session_id|**smallint**|ID of the session to which this request is related. Is not nullable.|
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```
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## See Also
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-[Dynamic Management Views and Functions](~/relational-databases/system-dynamic-management-views/system-dynamic-management-views.md)
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-[Execution Related Dynamic Management Views and Functions](../../relational-databases/system-dynamic-management-views/execution-related-dynamic-management-views-and-functions-transact-sql.md)
[Dynamic Management Views and Functions](~/relational-databases/system-dynamic-management-views/system-dynamic-management-views.md)
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[Execution Related Dynamic Management Views and Functions](../../relational-databases/system-dynamic-management-views/execution-related-dynamic-management-views-and-functions-transact-sql.md)
Returns one row for each task that is active in the instance of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)].
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Returns one row for each task that is active in the instance of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)]. For more information about tasks, see the [Thread and Task Architecture Guide](../../relational-databases/thread-and-task-architecture-guide.md).
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> [!NOTE]
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> To call this from [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)] or [!INCLUDE[ssPDW](../../includes/sspdw-md.md)], use the name **sys.dm_pdw_nodes_os_tasks**.
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> To call this from [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)] or [!INCLUDE[ssPDW](../../includes/sspdw-md.md)], use the name **sys.dm_pdw_nodes_os_tasks**.
|**pdw_node_id**|**int**|**Applies to**: [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)], [!INCLUDE[ssPDW](../../includes/sspdw-md.md)]<br /><br /> The identifier for the node that this distribution is on.|
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## Permissions
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On [!INCLUDE[ssNoVersion_md](../../includes/ssnoversion-md.md)], requires `VIEW SERVER STATE` permission.
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On [!INCLUDE[ssSDS_md](../../includes/sssds-md.md)] Premium Tiers, requires the `VIEW DATABASE STATE` permission in the database. On [!INCLUDE[ssSDS_md](../../includes/sssds-md.md)] Standard and Basic Tiers, requires the **Server admin** or an **Azure Active Directory admin** account.
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```
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## See Also
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[SQL Server Operating System Related Dynamic Management Views (Transact-SQL)](../../relational-databases/system-dynamic-management-views/sql-server-operating-system-related-dynamic-management-views-transact-sql.md)
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[SQL Server Operating System Related Dynamic Management Views (Transact-SQL)](../../relational-databases/system-dynamic-management-views/sql-server-operating-system-related-dynamic-management-views-transact-sql.md)
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[Thread and Task Architecture Guide](../../relational-databases/thread-and-task-architecture-guide.md)
Returns information about the wait queue of tasks that are waiting on some resource.
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Returns information about the wait queue of tasks that are waiting on some resource. For more information about tasks, see the [Thread and Task Architecture Guide](../../relational-databases/thread-and-task-architecture-guide.md).
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> [!NOTE]
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> To call this from [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)] or [!INCLUDE[ssPDW](../../includes/sspdw-md.md)], use the name **sys.dm_pdw_nodes_os_waiting_tasks**.
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On [!INCLUDE[ssSDS_md](../../includes/sssds-md.md)] Premium Tiers, requires the `VIEW DATABASE STATE` permission in the database. On [!INCLUDE[ssSDS_md](../../includes/sssds-md.md)] Standard and Basic Tiers, requires the **Server admin** or an **Azure Active Directory admin** account.
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## Example
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This example will identify blocked sessions. Execute the [!INCLUDE[tsql](../../includes/tsql-md.md)] query in [!INCLUDE[ssManStudioFull](../../includes/ssmanstudiofull-md.md)].
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This example will identify blocked sessions. Execute the [!INCLUDE[tsql](../../includes/tsql-md.md)] query in [!INCLUDE[ssManStudioFull](../../includes/ssmanstudiofull-md.md)].
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```sql
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SELECT*FROMsys.dm_os_waiting_tasks
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WHERE blocking_session_id IS NOT NULL;
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```
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## See Also
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[SQL Server Operating System Related Dynamic Management Views (Transact-SQL)](../../relational-databases/system-dynamic-management-views/sql-server-operating-system-related-dynamic-management-views-transact-sql.md)
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[Thread and Task Architecture Guide](../../relational-databases/thread-and-task-architecture-guide.md)
Returns a row for every worker in the system. For more information about workers, see the [Thread and Task Architecture Guide](../../relational-databases/thread-and-task-architecture-guide.md).
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> [!NOTE]
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> To call this from [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)] or [!INCLUDE[ssPDW](../../includes/sspdw-md.md)], use the name **sys.dm_pdw_nodes_os_workers**.
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In the output, when `w_runnable` and `w_suspended` are equal, this represents the time that the worker is in the SUSPENDED state. Otherwise, `w_runnable` represents the time that is spent by the worker in the RUNNABLE state. In the output, session `52` is `SUSPENDED` for `35,094` milliseconds.
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## See Also
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[SQL Server Operating System Related Dynamic Management Views (Transact-SQL)](../../relational-databases/system-dynamic-management-views/sql-server-operating-system-related-dynamic-management-views-transact-sql.md)
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[SQL Server Operating System Related Dynamic Management Views (Transact-SQL)](../../relational-databases/system-dynamic-management-views/sql-server-operating-system-related-dynamic-management-views-transact-sql.md)
This function returns the name of the time zone observed by a server or an instance. For [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)]`CURRENT_TIMEZONE` derives the return value from the operating system of the computer on which the instance of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] runs. For SQL Database Managed Instance return value is based on the time zone of the instance itself assigned during instance creation, not the time zone of the underlying operating system.
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This function returns the name of the time zone observed by a server or an instance. For SQL Database Managed Instance, return value is based on the time zone of the instance itself assigned during instance creation, not the time zone of the underlying operating system.
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> [!NOTE]
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> For single and pooled SQL Databases time zone is always set to UTC and `CURRENT_TIMEZONE` returns the name of the UTC time zone.
Copy file name to clipboardExpand all lines: docs/t-sql/spatial-geography/point-geography-data-type.md
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---
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title: "Point (geography Data Type) | Microsoft Docs"
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ms.custom: ""
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ms.date: "07/30/2017"
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ms.date: "10/10/2019"
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ms.prod: sql
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ms.prod_service: "database-engine, sql-database"
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ms.reviewer: ""
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Is a **float** expression representing the y-coordinate of the **Point** being generated. For more information on valid latitude and longitude values, see [Point](../../relational-databases/spatial/point.md).
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*SRID*
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Is an **int** expression representing the SRID of the **geography** instance you wish to return.
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Is an **int** expression representing the [Spatial Reference Identifier](https://docs.microsoft.com/sql/relational-databases/spatial/spatial-reference-identifiers-srids) of the **geography** instance you wish to return.
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