N'SELECT * FROM HumanResources.Employee WHERE EmployeeID = @IDParameter';
Each parameter included in @stmt must have a corresponding entry in both the @params parameter definition list and the parameter values list.
[ @params = ] N'@parameter_name data_type [ ,... n ]'
A string that contains the definitions of all parameters that are embedded in @stmt. The string must be either a Unicode constant or a Unicode variable. Each parameter definition consists of a parameter name and a data type. n is a placeholder that indicates more parameter definitions. Every parameter specified in @stmt must be defined in @params. If the Transact-SQL statement or batch in @stmt doesn't contain parameters, @params isn't required. The default value for this parameter is NULL.
[ @param1 = ] 'value1'
A value for the first parameter that is defined in the parameter string. The value can be a Unicode constant or a Unicode variable. There must be a parameter value supplied for every parameter included in @stmt. The values aren't required when the Transact-SQL statement or batch in @stmt has no parameters.
{ OUT | OUTPUT }
Indicates that the parameter is an output parameter. text, ntext, and image parameters can be used as OUTPUT parameters, unless the procedure is a common language runtime (CLR) procedure. An output parameter that uses the OUTPUT keyword can be a cursor placeholder, unless the procedure is a CLR procedure.
[ ... n ]
A placeholder for the values of extra parameters. Values can only be constants or variables. Values can't be more complex expressions such as functions, or expressions built by using operators.
Return code values
0 (success) or non-zero (failure).
Result set
Returns the result sets from all the SQL statements built into the SQL string.
sp_executesql parameters must be entered in the specific order as described in the Syntax section earlier in this article. If the parameters are entered out of order, an error message occurs.
sp_executesql has the same behavior as EXECUTE regarding batches, the scope of names, and database context. The Transact-SQL statement or batch in the sp_executesql @stmt parameter isn't compiled until the sp_executesql statement is executed. The contents of @stmt are then compiled and executed as an execution plan separate from the execution plan of the batch that called sp_executesql. The sp_executesql batch can't reference variables declared in the batch that calls sp_executesql. Local cursors or variables in the sp_executesql batch aren't visible to the batch that calls sp_executesql. Changes in database context last only to the end of the sp_executesql statement.
sp_executesql can be used instead of stored procedures to execute a Transact-SQL statement many times when the change in parameter values to the statement is the only variation. Because the Transact-SQL statement itself remains constant and only the parameter values change, the SQL Server query optimizer is likely to reuse the execution plan it generates for the first execution. In this scenario, performance is equivalent to that of a stored procedure.
To improve performance, use fully qualified object names in the statement string.
sp_executesql supports the setting of parameter values separately from the Transact-SQL string, as shown in the following example.
DECLARE @IntVariable INT;
DECLARE @SQLString NVARCHAR(500);
DECLARE @ParmDefinition NVARCHAR(500);
/* Build the SQL string once */
SET @SQLString = N'SELECT BusinessEntityID, NationalIDNumber, JobTitle, LoginID
FROM AdventureWorks2022.HumanResources.Employee
WHERE BusinessEntityID = @BusinessEntityID';
SET @ParmDefinition = N'@BusinessEntityID tinyint';
/* Execute the string with the first parameter value. */
SET @IntVariable = 197;
EXECUTE sp_executesql @SQLString,
@ParmDefinition,
@BusinessEntityID = @IntVariable;
/* Execute the same string with the second parameter value. */
SET @IntVariable = 109;
EXECUTE sp_executesql @SQLString,
@ParmDefinition,
@BusinessEntityID = @IntVariable;
Output parameters can also be used with sp_executesql. The following example retrieves a job title from the HumanResources.Employee table in the AdventureWorks2022 sample database, and returns it in the output parameter @max_title.
DECLARE @IntVariable INT;
DECLARE @SQLString NVARCHAR(500);
DECLARE @ParmDefinition NVARCHAR(500);
DECLARE @max_title VARCHAR(30);
SET @IntVariable = 197;
SET @SQLString = N'SELECT @max_titleOUT = max(JobTitle)
FROM AdventureWorks2022.HumanResources.Employee
WHERE BusinessEntityID = @level';
SET @ParmDefinition = N'@level TINYINT, @max_titleOUT VARCHAR(30) OUTPUT';
EXECUTE sp_executesql @SQLString,
@ParmDefinition,
@level = @IntVariable,
@max_titleOUT = @max_title OUTPUT;
SELECT @max_title;
Being able to substitute parameters in sp_executesql offers the following advantages over using the EXECUTE statement to execute a string:
Because the actual text of the Transact-SQL statement in the sp_executesql string doesn't change between executions, the query optimizer probably matches the Transact-SQL statement in the second execution with the execution plan generated for the first execution. Therefore, SQL Server doesn't have to compile the second statement.
The Transact-SQL string is built only once.
The integer parameter is specified in its native format. Casting to Unicode isn't required.
Permissions
Requires membership in the public role.
Examples
A. Execute a SELECT statement
The following example creates and executes a SELECT statement that contains an embedded parameter named @level.
EXECUTE sp_executesql
N'SELECT * FROM AdventureWorks2022.HumanResources.Employee
WHERE BusinessEntityID = @level',
N'@level TINYINT',
@level = 109;
B. Execute a dynamically built string
The following example shows using sp_executesql to execute a dynamically built string. The example stored procedure is used to insert data into a set of tables that are used to partition sales data for a year. There's one table for each month of the year that has the following format:
CREATE TABLE May1998Sales (
OrderID INT PRIMARY KEY,
CustomerID INT NOT NULL,
OrderDate DATETIME NULL CHECK (DATEPART(yy, OrderDate) = 1998),
OrderMonth INT CHECK (OrderMonth = 5),
DeliveryDate DATETIME NULL,
CHECK (DATEPART(mm, OrderDate) = OrderMonth)
This sample stored procedure dynamically builds and executes an INSERT statement to insert new orders into the correct table. The example uses the order date to build the name of the table that should contain the data, and then incorporates that name into an INSERT statement.
This is a basic example for sp_executesql. The example doesn't contain error checking, and doesn't include checks for business rules, such as guaranteeing that order numbers aren't duplicated between tables.
CREATE PROCEDURE InsertSales @PrmOrderID INT,
@PrmCustomerID INT,
@PrmOrderDate DATETIME,
@PrmDeliveryDate DATETIME
DECLARE @InsertString NVARCHAR(500);
DECLARE @OrderMonth INT;
-- Build the INSERT statement.
SET @InsertString = 'INSERT INTO ' +
/* Build the name of the table. */
SUBSTRING(DATENAME(mm, @PrmOrderDate), 1, 3) +
CAST(DATEPART(yy, @PrmOrderDate) AS CHAR(4)) + 'Sales' +
/* Build a VALUES clause. */
' VALUES (@InsOrderID, @InsCustID, @InsOrdDate,' +
' @InsOrdMonth, @InsDelDate)';
/* Set the value to use for the order month because
functions are not allowed in the sp_executesql parameter
list. */
SET @OrderMonth = DATEPART(mm, @PrmOrderDate);
EXEC sp_executesql @InsertString,
N'@InsOrderID INT, @InsCustID INT, @InsOrdDate DATETIME,
@InsOrdMonth INT, @InsDelDate DATETIME',
@PrmOrderID,
@PrmCustomerID,
@PrmOrderDate,
@OrderMonth,
@PrmDeliveryDate;
Using sp_executesql in this procedure is more efficient than using EXECUTE to execute a string. When sp_executesql is used, there are only 12 versions of the INSERT string that are generated, one for each monthly table. With EXECUTE, each INSERT string is unique because the parameter values are different. Although both methods generate the same number of batches, the similarity of the INSERT strings generated by sp_executesql makes it more likely that the query optimizer reuses execution plans.
C. Use the OUTPUT parameter
The following example uses an OUTPUT parameter to store the result set generated by the SELECT statement in the @SQLString parameter. Two SELECT statements are then executed that use the value of the OUTPUT parameter.
USE AdventureWorks2022;
DECLARE @SQLString NVARCHAR(500);
DECLARE @ParmDefinition NVARCHAR(500);
DECLARE @SalesOrderNumber NVARCHAR(25);
DECLARE @IntVariable INT;
SET @SQLString = N'SELECT @SalesOrderOUT = MAX(SalesOrderNumber)
FROM Sales.SalesOrderHeader
WHERE CustomerID = @CustomerID';
SET @ParmDefinition = N'@CustomerID INT,
@SalesOrderOUT NVARCHAR(25) OUTPUT';
SET @IntVariable = 22276;
EXECUTE sp_executesql @SQLString,
@ParmDefinition,
@CustomerID = @IntVariable,
@SalesOrderOUT = @SalesOrderNumber OUTPUT;
-- This SELECT statement returns the value of the OUTPUT parameter.
SELECT @SalesOrderNumber;
-- This SELECT statement uses the value of the OUTPUT parameter in
-- the WHERE clause.
SELECT OrderDate,
TotalDue
FROM Sales.SalesOrderHeader
WHERE SalesOrderNumber = @SalesOrderNumber;
Examples: Azure Synapse Analytics and Analytics Platform System (PDW)
D. Execute a SELECT statement
The following example creates and executes a SELECT statement that contains an embedded parameter named @level.
EXECUTE sp_executesql
N'SELECT * FROM AdventureWorksPDW2012.dbo.DimEmployee
WHERE EmployeeKey = @level',
N'@level TINYINT',
@level = 109;
Related content
EXECUTE (Transact-SQL)
System stored procedures (Transact-SQL)
