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sp_get_query_template (Transact-SQL)

Applies to: SQL Server

Returns the parameterized form of a query. The results returned mimic the parameterized form of a query that results from using forced parameterization. sp_get_query_template is used primarily when you create TEMPLATE plan guides.

Transact-SQL syntax conventions

Syntax

sp_get_query_template
   [ @querytext = ] N'querytext'
   , @templatetext OUTPUT
   , @parameters OUTPUT
[ ; ]

Arguments

[ @querytext = ] N'querytext'

The query for which the parameterized version is to be generated. @querytext is nvarchar(max), and must be enclosed in single quotation marks and be preceded by the N Unicode specifier.

@templatetext

An OUTPUT parameter of type nvarchar(max), provided as indicated, to receive the parameterized form of @querytext as a string literal.

@parameters

An output parameter of type nvarchar(max), provided as indicated, to receive a string literal of the parameter names and data types that are parameterized in @templatetext.

Remarks

sp_get_query_template returns an error when the following occur:

  • It doesn't parameterize any constant literal values in @querytext.
  • @querytext is NULL, not a Unicode string, syntactically not valid, or can't be compiled.

If sp_get_query_template returns an error, it doesn't modify the values of the @templatetext and @parameters output parameters.

Permissions

Requires membership in the public database role.

Examples

The following example returns the parameterized form of a query that contains two constant literal values.

USE AdventureWorks2022;
GO

DECLARE @my_templatetext NVARCHAR(MAX);
DECLARE @my_parameters NVARCHAR(MAX);

EXEC sp_get_query_template N'SELECT pi.ProductID, SUM(pi.Quantity) AS Total
        FROM Production.ProductModel pm
        INNER JOIN Production.ProductInventory pi
        ON pm.ProductModelID = pi.ProductID
        WHERE pi.ProductID = 2
        GROUP BY pi.ProductID, pi.Quantity
        HAVING SUM(pi.Quantity) > 400',
    @my_templatetext OUTPUT,
    @my_parameters OUTPUT;

SELECT @my_templatetext;
SELECT @my_parameters;

Here are the parameterized results of the @my_templatetext OUTPUT parameter:

select pi . ProductID , SUM ( pi . Quantity ) as Total
from Production . ProductModel pm
inner join Production . ProductInventory pi
on pm . ProductModelID = pi . ProductID
where pi . ProductID = @0
group by pi . ProductID , pi . Quantity
having SUM ( pi . Quantity ) > 400

The first constant literal, 2, is converted to a parameter. The second literal, 400, isn't converted because it's inside a HAVING clause. The results returned by sp_get_query_template mimic the parameterized form of a query when the PARAMETERIZATION option of ALTER DATABASE is set to FORCED.

Here are the parameterized results of the @my_parameters OUTPUT parameter:

@0 int

The order and naming of parameters in the output of sp_get_query_template can change between quick-fix engineering, service pack, and version upgrades of SQL Server. Upgrades can also cause a different set of constant literals to be parameterized for the same query, and different spacing to be applied in the results of both output parameters.