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sp_control_plan_guide (Transact-SQL)

  • Статия

Applies to: SQL Server

The sp_control_plan_guide system stored procedure is used to drop, enable, or disable a plan guide.

Transact-SQL syntax conventions

Syntax

sp_control_plan_guide
    [ @operation = ] { N'DROP [ ALL ]' | N'DISABLE [ ALL ]' | N'ENABLE [ ALL ]' }
    [ , [ @name = ] N'name' ]
[ ; ]

Arguments

[ @name = ] N'name'

Specifies the plan guide that is being dropped, enabled, or disabled. @name is sysname, with a default of NULL. @name is resolved to the current database. If not specified, @name defaults to NULL.

[ @operation = ] { N'DROP [ ALL ]' | N'DISABLE [ ALL ]' | N'ENABLE [ ALL ]' }

The operation to perform on the plan guide specified in @name. @operation is nvarchar(60), with no default.

  • DROP

    Drops the plan guide specified by @name. After a plan guide is dropped, future executions of a query formerly matched by the plan guide aren't influenced by the plan guide.

  • DROP ALL

    Drops all plan guides in the current database. @name can't be specified when DROP ALL is specified.

  • DISABLE

    Disables the plan guide specified by @name. After a plan guide is disabled, future executions of a query formerly matched by the plan guide aren't influenced by the plan guide.

  • DISABLE ALL

    Disables all plan guides in the current database. @name can't be specified when DISABLE ALL is specified.

  • ENABLE

    Enables the plan guide specified by @name. A plan guide can be matched with an eligible query after it's enabled. By default, plan guides are enabled at the time they're created.

  • ENABLE ALL

    Enables all plan guides in the current database. @name can't be specified when ENABLE ALL is specified.

Remarks

Trying to drop or modify a function, stored procedure, or DML trigger that is referenced by a plan guide, either enabled or disabled, causes an error.

Disabling a disabled plan guide or enabling an enabled plan guide has no effect and runs without error.

Plans guides aren't available in every edition of SQL Server. For a list of features that are supported by the editions of SQL Server, see Editions and supported features of SQL Server 2022. However, you can execute sp_control_plan_guide with the DROP or DROP ALL option in any edition of SQL Server.

Permissions

Executing sp_control_plan_guide on a plan guide of type OBJECT (created specifying @type = '<object>') requires ALTER permission on the object that is referenced by the plan guide. All other plan guides require ALTER DATABASE permission.

Examples

A. Enable, disable, and drop a plan guide

The following example creates a plan guide, disables it, enables it, and drops it.

--Create a procedure on which to define the plan guide.
IF OBJECT_ID(N'Sales.GetSalesOrderByCountry', N'P') IS NOT NULL
    DROP PROCEDURE Sales.GetSalesOrderByCountry;
GO

CREATE PROCEDURE Sales.GetSalesOrderByCountry (@Country NVARCHAR(60))
AS
BEGIN
    SELECT *
    FROM Sales.SalesOrderHeader AS h
    INNER JOIN Sales.Customer AS c
        ON h.CustomerID = c.CustomerID
    INNER JOIN Sales.SalesTerritory AS t
        ON c.TerritoryID = t.TerritoryID
    WHERE t.CountryRegionCode = @Country;
END
GO

--Create the plan guide.
EXEC sp_create_plan_guide N'Guide3',
    N'SELECT *
    FROM Sales.SalesOrderHeader AS h
    INNER JOIN Sales.Customer AS c
        ON h.CustomerID = c.CustomerID
    INNER JOIN Sales.SalesTerritory AS t
        ON c.TerritoryID = t.TerritoryID
    WHERE t.CountryRegionCode = @Country',
    N'OBJECT',
    N'Sales.GetSalesOrderByCountry',
    NULL,
    N'OPTION (OPTIMIZE FOR (@Country = N''US''))';
GO

--Disable the plan guide.
EXEC sp_control_plan_guide N'DISABLE',
    N'Guide3';
GO

--Enable the plan guide.
EXEC sp_control_plan_guide N'ENABLE',
    N'Guide3';
GO

--Drop the plan guide.
EXEC sp_control_plan_guide N'DROP',
    N'Guide3';
GO

B. Disable all plan guides in the current database

The following example disables all plan guides in the AdventureWorks2022 database.

USE AdventureWorks2022;
GO
EXEC sp_control_plan_guide N'DISABLE ALL';

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